Exhibit 24

                                Power of Attorney

Know all by these presents, that the undersigned hereby makes, constitutes and
appoints each of Mark J. Casey, Bryan M. Reasons and Daniel J. Speciale, or any
of them acting singly, and with full power of substitution and re-substitution,
the undersigned's true and lawful attorney-in-fact (each of such persons and
their substitutes being referred to herein as the "Attorney-in-Fact"), with
full power to act for the undersigned and in the undersigned's name, place and
stead, in any and all capacities, to:

     1.   Prepare, execute, and submit to the Securities and Exchange
          Commission ("SEC") a Form ID, including amendments thereto, and any
          other documents necessary or appropriate to obtain codes and
          passwords enabling the undersigned to make electronic filings with
          the SEC of reports required or considered by the Attorney-in-Fact to
          be advisable under Section 13 or Section 16 of the Securities
          Exchange Act of 1934 (the "Exchange Act") or any rule or regulation
          of the SEC;

     2.   Prepare, execute and submit to the SEC, Mallinckrodt plc (the
          "Company"), and/or any national securities exchange on which the
          Company's securities are listed any and all reports (including any
          amendments thereto) the undersigned is required to file with the SEC,
          or which the Attorney-in-Fact considers it advisable to file with the
          SEC, under Section 13 or Section 16 of the Exchange Act or any rule
          or regulation thereunder, or under Rule 144 under the Securities Act
          of 1933 ("Rule 144"), with respect to the any security of the
          Company, including Forms 3, 4 and 5, Schedules 13D and 13G, and Forms
          144;

     3.   Prepare, execute and submit to Irish Companies Registration Office
          and/or any other authority ("CRO") any and all reports, filings or
          other disclosures (including any amendments thereto) related to the
          undersigned's holdings of and transactions in securities of the
          Company that the undersigned is required to file with the CRO, or
          which the Attorney-in-Fact considers it advisable to file with the
          CRO pursuant to the Companies Act 2014 of Ireland (the "Companies
          Act"); and

     4.   Obtain, as the undersigned's representative and on the undersigned's
          behalf, information regarding transactions in the Company's equity
          securities from any third party, including the Company and any
          brokers, dealers, employee benefit plan administrators and trustees,
          and the undersigned hereby authorizes any such third party to release
          any such information to the Attorney-in-Fact.

The undersigned acknowledges that:

     (a)  This Power of Attorney authorizes, but does not require, the
          Attorney-in-Fact to act in his or her discretion on information
          provided to such Attorney-in-Fact without independent verification of
          such information;

     (b)  Any documents prepared or executed by the Attorney-in-Fact on behalf
          of the undersigned pursuant to this Power of Attorney will be in such
          form and will contain such information as the Attorney-in-Fact, in
          his or her discretion, deems necessary or desirable;

     (c)  Neither the Company nor the Attorney-in-Fact assumes any liability
          for the undersigned's responsibility to comply with the requirements
          of the Companies Act or Section 13 or Section 16 of the Exchange Act
          or Rule 144, any liability of the undersigned for any failure to
          comply with such requirements, or any liability of the undersigned
          for disgorgement of profits under Section 16(b) of the Exchange Act;
          and

     (d)  This Power of Attorney does not relieve the undersigned from
          responsibility for compliance with the undersigned's obligations
          under the Companies Act or Section 13 or Section 16 of the Exchange
          Act, including, without limitation, the reporting requirements under
          Section 13 or Section 16 of the Exchange Act.

The undersigned hereby grants to the Attorney-in-Fact full power and authority
to do and perform each and every act and thing requisite, necessary or
advisable to be done in connection with the foregoing, as fully, to all intents
and purposes, as the undersigned might or could do in person, hereby ratifying
and confirming all that the Attorney-in-Fact, or his or her substitute or
substitutes, shall lawfully do or cause to be done by authority of this Power
of Attorney.

This Power of Attorney shall remain in full force and effect until the
undersigned is no longer required to file Forms 4 or 5 or Schedules 13D or 13G
or Forms 144 and make disclosure under the Companies Act with respect to the
undersigned's holdings of and transactions in securities of the Company, unless
earlier revoked by the undersigned in a signed writing delivered to the
Attorney-in-Fact. This Power of Attorney revokes all previous powers of
attorney with respect to the subject matter of this Power of Attorney.

IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney as of
April 6, 2022.

/s/ Daniel A. Celentano
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Daniel A. Celentano