Generally speaking, acclaimed film or television actors will sometimes do a season on Broadway, and the results can be really surprising — an actor not known for singing is cast in the lead of a musical, for instance. Cynics will say that this is a ploy for flagging shows to bring in a wider audience, but sometimes the actor fits the role and fits into the show very well, indeed.
Christy Carlson Romano took the role of Kate/Lucy in Avenue Q. There is something a bit jarring in hearing Kim Possible cry "f* ck, it sucks to be me".
Andrea McArdle, the original Annie, has returned to show business and now plays the nasty Miss Hannigan.
In 1980, David Bowie — he of the sultry voice, smooth onstage moves, and cool persona — made his Broadway debut as the title character in The Elephant Man. Beyond the role being that of The Grotesque, it is a notorious challenge for an actor, since the script's instructions dictate that he must rely on twisted body language and vocal distortion rather than makeup to convey his severe deformities. As well, no established rock star had appeared in a Broadway show (much less a non-musical) up to that point, and critics were doubtful this would work — but Bowie got excellent reviews from them all the same. And film director Nagisa Oshima cast Bowie in Merry Christmas, Mr. Lawrence after seeing him in this play.
Laurence Fishburne, known for playing serious, stoic types, played the title role in Thurgood, a one-man-play about Supreme Court justice Thurgood Marshall, who was something of a Boisterous Bruiser.
The otherwise light-hearted Opal Peachey plays a naughty leather-clad character in Modern Luv.
Adamo Ruggiero, known for playing gay characters (most notably Marco del Rossi), played the stoner Van in a production of Dog Sees God Confessions Of A Teenage Blockhead, and outright asks a female character for a blowjob. Adamo even noted that when he was asked to audition, he expected to read for Beethoven, the kid who gets picked on because everyone thinks he's gay.