They'll join original cast members Roger Bart, Shuler Hensley, Fred Applegate and Christopher Fitzgerald. Sullivan will assume the role of wide-eyed Inga on July 8, replacing Sutton Foster (who is now in rehearsals for Shrek and exits the Hilton July 6); Tony winner Beth Leavel (The Drowsy Chaperone) will become Germanic Frau Blucher on July 22 and Ragusa (Adrift in Macao, Paper Mill's Kiss Me, Kate) takes over the role of Elizabeth, the cold girlfriend of the title character, on Aug. 5.

Andrea Martin — Tony-nominated for her performance — completes her Weill-esque turn July 20 and Megan Mullally (as Elizabeth) will depart after the Aug. 3 performance.

Young Frankenstein, with book by Brooks and Thomas Meehan and music and lyrics by Brooks, was named Best Broadway Musical 2008 by the Outer Critics Circle Award.

The musical comedy is based on the Oscar-nominated hit 1974 film of the same name. It's "the wickedly inspired re-imagining of the Mary Shelley classic from the comic genius of Mel Brooks," according to producers. "When Frederick Frankenstein, an esteemed New York brain surgeon and professor, inherits a castle and laboratory in Transylvania from his grandfather, deranged genius Victor Von Frankenstein, he faces a dilemma. Does he continue to run from his family's tortured past or does he stay in Transylvania to carry on his grandfather's mad experiments reanimating the dead and, in the process, fall in love with his sexy lab assistant Inga?"

Set in "the forbidding Castle Frankenstein and the foggy moors of Transylvania Heights," the show's score includes "The Transylvania Mania," "He Vas My Boyfriend" and a singular treatment of Irving Berlin's "Puttin' On the Ritz." For information, visit YoungFrankensteinTheMusical.com or Ticketmaster.com or call (212) 307-4100.