John Mahoney (1940 - ) dressed as Sherlock Holmes for a Halloween Party on the hit comedy "Frasier" in which he played Martin Crane, Frasier (Kesley Grammer) Crane's Father.
The episode (Series 5, Episode 3 "Halloween"), sees Niles Crane pick out a costume for Martin so he can be the aristocratic detective "Lord Peter Whimsy".
Martin does not think much to the idea and simply replys: "Well, I'm not going anywhere where I have to tell people my name's Whimsy! I want to be Sherlock Holmes!"
And so for the rest of the episode - he is!