Stephen Sondheim's 85th birthday will get a Royal Albert Hall blowout.
Brynn O'Malley from Honeymoon in Vegas and Mary Beth Peil from Dying for It also join the conversation.
The Tony Award winner was most recently seen on Broadway in the 2001 revival of Follies.
Watch the handsome Smash and Newsies star croon the classic song from Follies at 54 Below.
The stage and screen favorite was most recently seen on Broadway in Follies and Six Dance Lessons in Six Weeks.
Mallory, who was 64, had been battling pancreatic cancer.
The Tony-winning actress will be joined by Grammy-winning composer Billy Stritch.