MET INVESTORS SERIES    TRUST SUMMARY PROSPECTUS    April 29, 2013

AQR Global Risk Balanced Portfolio

Class B Shares

Before you invest, you may want to review the Portfolio’s Prospectus, which contains more information about the Portfolio and its risks. You can find the Portfolio’s Prospectus and other information about the Portfolio (including the documents listed below) online at www.metlife.com/variablefunds. You can also get this information at no cost by calling 1-800-638-7732 or by sending an e-mail request to RCG@metlife.com. The Portfolio’s Prospectus and Statement of Additional Information, both dated April 29, 2013, and the Portfolio’s financial statements for the year ended December 31, 2012, including the notes to the financial statements, the financial highlights and the report of the Portfolio’s independent registered public accounting firm, all of which are included in the Annual Report of the Portfolio, dated December 31, 2012, are all incorporated by reference into this Summary Prospectus. This Summary Prospectus is intended for individuals who have purchased certain variable life insurance policies and variable annuity contracts (collectively, “Contracts”) from Metropolitan Life Insurance Company and its affiliates and is not intended for use by other investors.

Investment Objective

Seeks total return.

Fees and Expenses of the Portfolio

The following table describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio. The table and the Example below do not reflect the fees, expenses or withdrawal charges imposed by the Contracts. If Contract expenses were reflected, the fees and expenses in the table and Example would be higher. See the Contract prospectus for a description of those fees, expenses and charges.

Shareholder Fees (fees paid directly from your investment)—None

Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

	Class B
Management Fee	0.61%
Distribution and/or Service (12b-1) Fees	0.25%
Other Expenses	0.12%
Interest Expense	0.09%
All Other Expenses	0.03%
Acquired Fund Fees and Expenses	0.06%
Total Annual Portfolio Operating Expenses	1.04%
Fee Waiver*	(0.01%)
Net Operating Expenses	1.03%

* MetLife Advisers, LLC has contractually agreed, for the period April 29, 2013 through April 30, 2014, to reduce the Management Fee to the annual rate of 0.675% of the first $250 million of the Portfolio’s average daily net assets, 0.650% of such assets over $250 million up to $750 million, 0.625% of such assets over $750 million up to $1 billion, 0.600% of such assets over $1 billion up to $3.5 billion and 0.570% of such assets over $3.5 billion. This arrangement may be modified or discontinued prior to April 30, 2014, only with the approval of the Board of Trustees of the Portfolio.

Example

The following Example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year, that the Portfolio’s operating expenses remain the same and that all fee waivers for the Portfolio will expire after one year. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:

	1 Year		3 Years		5 Years		10 Years
Class B	$	106	$	332	$	576	$	1,275

Portfolio Turnover

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual portfolio operating expenses or in the Example, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 79% of the average value of its portfolio.

Principal Investment Strategies

The Portfolio utilizes an investment strategy designed to generate returns from a risk diversified portfolio of asset exposures. The Portfolio targets an equal or “neutral” risk allocation from each of the following three major risk sources: (i) equity risk; (ii) nominal interest rate risk (a nominal interest rate is the sum of a real interest rate and an expected inflation rate); and (iii) inflation risk. Targeting a “neutral” risk allocation means that AQR Capital Management, LLC (“AQR”), subadviser to the Portfolio, will target for the Portfolio an equal one-third exposure to each of equity risk, nominal interest rate risk, and inflation risk. The allocation among asset classes is based solely on AQR’s assessment of the risks associated with each asset class, and AQR will adjust the exposure level to respective asset classes as its forecasts of the

risk environment change. The Portfolio’s “risk balanced” strategy is managed to target a specific risk level as discussed below.

In seeking to balance the Portfolio’s risks, AQR allocates the Portfolio’s assets among the following major asset classes: global developed and emerging market equities, global nominal and inflation-linked government bonds, and commodities. The face value of an inflation-linked bond rises along with the rate of inflation, while the face value of a nominal bond does not. It is anticipated that the Portfolio’s exposure to equities will primarily be achieved through investments in index futures, swaps on equity index futures and/or equity total return swaps. Nominal bond and commodities exposures will principally be achieved through investments in futures and swaps on futures. Futures and forward contracts are contractual agreements to buy or sell a particular currency, commodity or financial instrument at a pre-determined price in the future. The Portfolio will have exposure to inflation-linked bonds either purchased directly or financed by reverse repurchase agreements. In order to hedge the Portfolio’s currency risk associated with direct investments in these Instruments, AQR may choose to make investments in currency forwards and/or futures contracts. For more information about the types of investments in which the Portfolio may invest, please see “Investment Strategies and Risks” in the Statement of Additional Information.

The Portfolio intends to gain exposure to these asset classes by investing in a portfolio of over 40 Instruments (as defined below). The Portfolio is non-diversified, which means that it can hold securities of a smaller number of issuers and can invest a larger percentage of its assets in a single issuer than a diversified portfolio.

In allocating the Portfolio’s assets among equity risk, nominal interest rate risk, and inflation risk, AQR follows a “risk balanced” approach. The “risk balanced” approach to asset allocation seeks to balance the allocation of risk that is contributed by asset classes as measured by forecasted volatility, estimated potential loss, and other proprietary measures. For example, a lower risk asset class such as developed government bonds will generally have a greater exposure in the Portfolio than a higher risk asset class such as developed equities. In targeting this equal risk allocation, AQR may utilize leverage to increase the Portfolio’s relative exposure to its lower risk asset classes.

Generally, the Portfolio gains exposure to asset classes through many types of investments, including, but not limited to: equity index futures, swaps on equity index futures, equity total return swaps, currency forwards, commodity futures, swaps on commodity futures, bond futures, swaps on bond futures, inflation swaps, government bonds, including inflation-protected government bonds (such as Treasury Inflation Protected Securities) either purchased directly or financed by reverse repurchase agreements, cash and cash equivalents including, but not limited to, money market fund shares (collectively, the “Instruments”), either by investing directly in those Instruments, or indirectly through its subsidiary as discussed below. The Portfolio may also invest in exchange-traded funds (“ETFs”) or exchange traded notes through which the Portfolio can participate in the performance of one or more instruments.

The Portfolio has no geographic limits on where its investments may be located or where its assets may be exposed, except that its investments in (and exposure to) fixed income securities will be limited to those issued by governments located in developed markets and its exposure to emerging markets equities will be limited to no more than 10% of its net assets. The Portfolio may invest in or have exposure to equity securities of companies of any market capitalization.

The Portfolio’s use of futures contracts, forward contracts, swaps and certain other Instruments will have the economic effect of financial leverage. Financial leverage magnifies exposure to the swings in prices of the asset class underlying those Instruments and results in increased volatility, which means the Portfolio will have the potential for greater gains, as well as the potential for greater losses, than if the Portfolio does not use Instruments that have a leveraging effect. Leveraging also tends to magnify, sometimes significantly, the effect of any increase or decrease in the Portfolio’s exposure to an asset class and may cause the Portfolio’s net asset value (“NAV”) to be volatile. There is no assurance that the Portfolio’s use of Instruments providing enhanced exposure will enable the Portfolio to achieve its investment objective. As a result of the Portfolio’s strategy, the Portfolio may at times have leveraged exposure to one or more asset classes. The Investment Company Act of 1940, as amended (the “1940 Act”), and the rules and interpretations thereunder impose certain limitations on the Portfolio’s ability to use leverage.

AQR normally will target an annualized volatility level for the Portfolio of 10%, however, the actual or realized volatility for longer or shorter periods may be materially higher or lower depending on market conditions. In addition, the Portfolio’s NAV may be volatile over short-term periods because of the significant use of Instruments that have a leveraging effect. Volatility is a statistical measurement of the magnitude of up and down fluctuations in the value of a financial instrument or index over time. High volatility may result from rapid and dramatic price swings. Actual or realized volatility can and will differ from the target volatility. Although an annualized volatility level of 10% is normally targeted for the Portfolio, AQR may, under certain market conditions, target a lower volatility level for the Portfolio. While AQR attempts to manage the Portfolio’s volatility exposure to stabilize performance, there can be no assurance that the Portfolio will reach the targeted volatility.

The Portfolio may allocate up to 25% of its total assets to its wholly-owned and controlled subsidiary, organized under the laws of the Cayman Islands as an exempted company (the “Subsidiary”). AQR also manages the assets of the Subsidiary. Generally, the Subsidiary will invest primarily in commodity futures and swaps on commodity futures but it may also invest in other commodity-related instruments such as financial futures, option and swap contracts, equity and fixed income securities, cash and cash equivalents, pooled investment vehicles, including those that are not registered pursuant to the 1940 Act, and other

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investments intended to serve as margin or collateral for the Subsidiary’s derivative positions. The Portfolio will invest in the Subsidiary in order to gain exposure to the commodities markets within the limitations of the federal tax laws, rules and regulations that apply to registered investment companies. Unlike the Portfolio, the Subsidiary may invest without limitation in commodity-linked derivatives; however, the Subsidiary will comply with the same 1940 Act asset coverage requirements with respect to its investments in commodity-linked derivatives that are applicable to the Portfolio’s transactions in derivatives. In addition, to the extent applicable to the investment activities of the Subsidiary, the Subsidiary will be subject to the same fundamental investment restrictions and will follow the same compliance policies and procedures as the Portfolio. The Portfolio is the sole shareholder of the Subsidiary and does not expect shares of the Subsidiary to be offered or sold to other investors.

A significant portion of the assets of the Portfolio may be invested directly or indirectly in money market instruments, which may include, but are not limited to, U.S. Government securities (including U.S. Treasury bills), U.S. Government agency securities, Eurodollar obligations, bankers’ acceptances, short-term fixed income securities, overnight and/or fixed term repurchase agreements, money market fund shares, and cash and cash equivalents with one year or less term to maturity. These cash or cash equivalent holdings serve as collateral for the positions the Portfolio takes and also earn income for the Portfolio. The Portfolio may also enter into reverse repurchase agreements. Under a reverse repurchase agreement, the Portfolio sells securities to another party and agrees to repurchase them at a particular date. While the Portfolio normally does not engage in borrowing, leverage will be created when the Portfolio enters into reverse repurchase agreements, engages in futures transactions or uses certain other derivative instruments.

Principal Risks

As with all mutual funds, there is no guarantee that the Portfolio will achieve its investment objective. You could lose money by investing in the Portfolio. An investment in the Portfolio through a Contract is not a deposit or obligation of, or guaranteed by, any bank, and is not federally insured by the Federal Deposit Insurance Corporation, the Federal Reserve Board, or any other agency of the U.S. Government.

The value of your investment in the Portfolio may be affected by one or more of the following risks, which are described in more detail in “Principal Risks of Investing in the Portfolio” in the Prospectus, any of which could cause the Portfolio’s return, the price of the Portfolio’s shares or the Portfolio’s yield to fluctuate. In addition, there can be no assurance that employing a “risk balanced” approach will achieve any particular level or return or will, in fact, reduce volatility or potential loss.

Information Risk.    When the quantitative models (“Models”) and information and data (“Data”) used in managing the Portfolio prove to be incorrect or incomplete, any investment decisions made in reliance on the Models and Data may not produce the desired results and the Portfolio may realize losses. In addition, any hedging based on faulty Models and Data may prove to be unsuccessful. Furthermore, the success of Models that are predictive in nature is dependent largely on the accuracy and reliability of the supplied historical data. All Models are susceptible to input errors which may cause the resulting information to be incorrect.

Market Risk.    The Portfolio’s share price can fall because of, among other things, a decline in the market as a whole, deterioration in the prospects for a particular industry or company, or changes in general economic conditions, such as prevailing interest rates and investor sentiment. Significant disruptions to the financial markets could adversely affect the liquidity and volatility of securities held by the Portfolio.

Interest Rate Risk.    The value of the Portfolio’s investments in fixed income securities may decline when prevailing interest rates rise or increase when interest rates go down. The longer a security’s maturity or duration, the greater its value will change in response to changes in interest rates. The interest earned on the Portfolio’s investments in fixed income securities may decline when prevailing interest rates decline.

TIPS and Inflation-Linked Bonds Risk.    The value of inflation-protected securities generally fluctuates in response to changes in real interest rates, which are in turn tied to the relationship between nominal interest rates and the rate of inflation. Therefore, if inflation were to rise at a faster rate than nominal interest rates, real interest rates might decline, leading to an increase in the value of inflation-protected securities. In contrast, if nominal interest rates increased at a faster rate than inflation, real interest rates might rise, leading to a decrease in the value of inflation-protected securities. When real interest rates are rising faster than nominal interest rates, inflation-indexed bonds, including Treasury Inflation Protected Securities, may experience greater losses than other fixed income securities with similar durations.

Commodities Risk.    Exposure to the commodities markets may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodities and commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity.

Credit and Counterparty Risk.    The value of the Portfolio’s investments may be adversely affected if a security’s credit rating is downgraded; an issuer of an investment held by the Portfolio fails to pay an obligation on a timely basis, otherwise defaults or is perceived by other investors to be less creditworthy; or a counterparty to a derivatives or other transaction with the Portfolio files for bankruptcy, becomes insolvent, or otherwise becomes unable or unwilling to honor its obligation to the Portfolio.

Forward and Futures Contract Risk.    The successful use of forward and futures contracts will depend upon the Subadviser’s skill and experience with respect to such instruments and are

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subject to special risk considerations. The primary risks associated with the use of forward and futures contracts are (i) the imperfect correlation between the change in market value of the instruments held by the Portfolio and the price of the forward or futures contract; (ii) possible lack of a liquid secondary market for a futures contract and the resulting inability to close a futures contract when desired; (iii) losses caused by unanticipated market movements, which are potentially unlimited; (iv) the Subadviser’s inability to predict correctly the direction of securities prices, interest rates, currency exchange rates and other economic factors; (v) the possibility that the counterparty to a forward contract will default in the performance of its obligations; and (vi) if the Portfolio has insufficient cash, it may have to sell securities to meet daily variation margin requirements on a futures contract, and the Portfolio may have to sell securities at a time when it may be disadvantageous to do so.

Derivatives Risk.    The Portfolio will primarily invest in derivatives, such as futures and forward contracts, and swaps, to seek exposure to certain asset classes and enhance returns. To a lesser extent, the Portfolio may also invest in derivatives to “hedge” or protect its assets from an unfavorable shift in the value or rate of a reference instrument. Derivatives can significantly increase the Portfolio’s exposure to market risk, credit and counterparty risk and other risks, as well as increase transaction costs. Derivatives may be illiquid and difficult to value. Because of their complex nature, some derivatives may not perform as intended. As a result, the Portfolio may not realize the anticipated benefits from a derivative it holds or it may realize losses. A risk of the Portfolio’s use of derivatives is that the fluctuations in their values may not correlate perfectly with the overall securities markets.

Leveraging Risk.    Derivatives and other transactions that give rise to leverage may cause the Portfolio’s performance to be more volatile than if the Portfolio had not been leveraged. Leveraging also may require that the Portfolio liquidate portfolio securities when it may not be advantageous to do so to satisfy its obligations. Leveraging may expose the Portfolio to losses in excess of the amounts invested or borrowed.

Investment Company and Exchange Traded Fund Risk.    An investment in an investment company or ETF involves substantially the same risks as investing directly in the underlying securities. An investment company or ETF may not achieve its investment objective or execute its investment strategy effectively, which may adversely affect the Portfolio’s performance. The Portfolio must pay its pro rata portion of an investment company’s or ETF’s fees and expenses. Shares of a closed-end investment company or ETF may trade at a premium or discount to the net asset value of its portfolio securities.

Volatility Management Risk.    Although the Portfolio’s Subadviser attempts to adjust the Portfolio’s overall exposure to volatility, there can be no guarantee that the Portfolio’s Subadviser will be successful in managing the Portfolio’s overall level of volatility. The Portfolio may not realize the anticipated benefits from its volatility management strategies or it may realize losses because of the investment techniques employed by the Subadviser to manage volatility, the implementation of those strategies by the Subadviser or the limitations of those strategies in times of extremely low volatility or extremely high volatility. Under certain market conditions, the use of volatility management strategies by the Subadviser may also result in less favorable performance than if such strategies had not been used.

Forward Commitment, When-Issued and Delayed Delivery Securities Risk.    Investments in forward commitments and when-issued and delayed delivery securities are subject to the risk that the value or yield of the securities the Portfolio is obligated to purchase may decline below the agreed upon purchase price or expected yield before the securities are actually issued or delivered. These investments may create a form of investment leverage, which may increase the Portfolio’s volatility and may require the Portfolio to liquidate portfolio securities when it may not be advantageous to do so.

Foreign Investment Risk.    Investments in foreign securities tend to be more volatile and less liquid than investments in U.S. securities because, among other things, they involve risks relating to political, social and economic developments abroad, as well as risks resulting from differences between the regulations and reporting standards and practices to which U.S. and foreign issuers are subject. To the extent foreign securities are denominated in foreign currencies, their values may be adversely affected by changes in currency exchange rates. All of the risks of investing in foreign securities are typically increased by investing in emerging market countries.

Repurchase Agreement Risk.    Repurchase agreements are subject to credit and counterparty risk. In the event a counterparty defaults, becomes insolvent or otherwise becomes unable or unwilling to honor its obligation to the Portfolio, the Portfolio may incur delays or restrictions on its ability to dispose of the underlying securities and lose all or a part of the income from the repurchase agreement.

Non-diversification Risk.    To the extent that the Portfolio holds securities of a smaller number of issuers or invests a larger percentage of its assets in a single issuer than a diversified portfolio, the value of the Portfolio, as compared to the value of a diversified portfolio, will generally be more volatile and more sensitive to the performance of any one of those issuers and to economic, political, market or regulatory events affecting any one of those issuers.

Subsidiary Risk.    By investing in the Subsidiary, the Portfolio is indirectly exposed to the commodities risks associated with the Subsidiary’s investments in commodity-related instruments. There can be no assurance that the Subsidiary’s investments will contribute to the Portfolio’s returns. The Subsidiary is not registered under the 1940 Act and is not subject to all the investor protections of the 1940 Act. Changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Portfolio and/or the Subsidiary to operate as described in this Prospectus and could adversely affect the Portfolio, such as by reducing the Portfolio’s investment returns.

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Market Capitalization Risk.    Exposure to issuers primarily in one market capitalization category (large, medium or small) carries the risk that due to current market conditions that category may be out of favor with investors. Larger, more established companies may be unable to respond quickly to new competitive challenges or attain the high growth rate of successful smaller companies. Stocks of smaller companies may be more volatile than those of larger companies due to, among other things, narrower product lines, more limited financial resources and fewer experienced managers. In addition, there is typically less publicly available information about small capitalization companies, and their stocks may have a more limited trading market than stocks of larger companies.

Asset Allocation Risk.    The Portfolio’s ability to achieve its investment objective depends upon AQR’s analysis of various factors and AQR’s ability to select the appropriate mix of asset classes based on its analysis of such factors, which may prove incorrect. The Portfolio may experience losses or poor relative performance if AQR allocates a significant portion of the Portfolio’s assets to an asset class that does not perform as AQR anticipated, including relative to other asset classes. The Portfolio may underperform funds that allocate their assets differently than the Portfolio.

Portfolio Turnover Risk.    The investment techniques and strategies utilized by the Portfolio might result in a high degree of portfolio turnover. High portfolio turnover rates will increase the Portfolio’s transaction costs, which can adversely affect the Portfolio’s performance.

Past Performance

The information below shows the volatility of the Portfolio’s returns from year to year and how the Portfolio’s average annual returns over time compare with those of a broad-based securities market index. Both the bar chart and table assume reinvestment of dividends and distributions. Note that the results in the bar chart and table do not include the effect of Contract charges. If these Contract charges had been included, performance would have been lower. As with all mutual funds, past returns are not a prediction of future returns.

Year-by-Year Total Return for Class B Shares as of December 31 of Each Year

Highest Quarter	3rd – 2012	6.05%
Lowest Quarter	2nd – 2012	-1.15%

Average Annual Total Return as of December 31, 2012
	1 Year	Since Inception	Inception Date
Class B	10.56%	8.34%	05-02-11
Dow Jones Moderate Index (reflects no deduction for mutual fund fees or expenses)	11.24%	3.09%	—

Management

Adviser.    MetLife Advisers, LLC (“MetLife Advisers”) is the Portfolio’s investment adviser.

Subadviser.    AQR Capital Management, LLC (the “Subadviser”) is the subadviser to the Portfolio.

Portfolio Managers.    Brian K. Hurst, Principal, Michael Mendelson, Principal, and Yao Hua Ooi, Principal, have each managed the Portfolio since inception.

Purchase and Sale of Portfolio Shares

Shares of the Portfolio are only sold to separate accounts of Metropolitan Life Insurance Company and its affiliates to fund Contracts. For information regarding the purchase and sale of the Portfolio’s shares, please see the prospectus for the relevant Contract.

Tax Information

For information regarding the tax consequences of Contract ownership, please see the prospectus for the relevant Contract.

Payments to Broker-Dealers and Other Financial Intermediaries

The Portfolio is not sold directly to the general public but instead is offered as an underlying investment option for Contracts issued by insurance companies that are affiliated with the Portfolio and MetLife Advisers. As a result of these affiliations, the insurance companies may benefit more from offering the Portfolio as an investment option in the Contracts than offering other unaffiliated portfolios. The Portfolio and its related companies may also make payments to the sponsoring insurance companies (or their affiliates) for distribution and/or other services. The benefits to the insurance companies of offering the Portfolio over unaffiliated portfolios and these payments may be factors that the insurance companies consider in including the Portfolio as an underlying investment option in the Contracts and may create a conflict of interest. The prospectus for your Contract contains additional information about these payments.

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