Nathan Lane guest stars as a man who steals Frasier's briefcase. The theft has Frasier (Kelsey Grammer) shaken to his foundations, not only because of the material loss, but because it has damaged his faith in mankind. But that's not the half of it: The thief is now going all over Seattle posing as Dr. Frasier Crane. And here's a puzzler for Frasier fans: Guess the identity of that uncredited celebrity who provides the call-in voice of Denise. ~ Hal Erickson, Rovi