Collins appeared on Broadway in the original productions of Michael Weller's Moonchildren, Terrence McNally's The Ritz, Christopher Durang's Beyond Therapy, and A.R. Gurney's The Old Boy. Off-Broadway, he appeared in Macbeth opposite Christopher Walken and was directed by Joseph Papp in Twelfth Night. Collins also directed a regional production of The Old Boy. His play Super Sunday was produced at the Williamstown Theatre Festival, where he acted opposite Blythe Danner in Noel Coward's Tonight at 8:30. In addition to Seventh Heaven, his many TV and film credits include Tattingers, A Woman Named Jackie, The First Wives' Club and The Two Mrs. Grenvilles.
Jonathan Hadary has been playing King Arthur in Spamalot for almost two years; Patsy is currently being played by David Hibbard.