Mr. Ainsley wasn't the first to sing the role of Herod — a decadent, mocking tyrant as written by composer Andrew Lloyd Webber and lyricist Tim Rice. That honor went to Mike d'Abo, a former lead singer of Manfred Mann, who voiced the cameo role on the original album of the score, which preceded the first stage production by a year. When it was time to cast the Broadway staging, however, Mr. Ainsley got the part.

Herod sings only one tune in the show — "King Herod's Song" — but it's a showstopper, a jazz-tinged vaudevillian number in which the supercilious king taunts Jesus will lyrics like "Prove to me that you're no fool/Walk across my swimming pool."

Following his Broadway stint — the sole such credit on his resume — Mr. Ainsley played the part on tour, in stock productions, in concert and at benefits. The Boston-born actor's other theatre career highlights included originating the part Thenardier in the third national company of Les Miserables, playing Mr. Darling/Captain Hook to Cathy Rigby's Peter Pan, succeeding Barry Bostwick and Jim Belushi as the Pirate King in Pirates of Penzance, and  playing Herbie to Karen Morrow's Rose in Gypsy. Mr. Ainsley was also a member of the Improvisational Theatre Project at the Mark Taper Forum.

On television, he played the usually mute Jim the Bartender on the sitcom "Three's Company."