Blumenkrantz will replace the show's composer Joe Kinosian.
The staged presentation also stars Jay Armstrong Johnson, Jeff Blumenkrantz, Christian Borle, and more.
Michael McElroy and Kenita Miller will complete the cast of the song cycle's world premiere.
Creators Joe Kinosian and Kellen Blair will also be on hand.
The event's cast will also include Jeff Blumenkrantz, Kyle Brenn, Jay Armstrong Johnson, and Philip Quast.
Brett Ryback and Jeff Blumenkrantz discuss embracing their unlikely comedic chemistry and learning the art of improvisation.
The holiday event featured performances by Jill Abramovitz, Brett Ryback, Lucy Braid, and more.
Kinosian will play opposite the show's current Marcus, Brett Ryback.
The new concert series will benefit Broadway Cares/Equity Fights AIDS.
The musical comedy stars Brett Ryback and Jeff Blumenkrantz as a detective and his many suspects.