In "The Rocker", what is Robert's nickname?

“In ‘The Rocker’, what is Robert’s nickname?” The answer is Fish. Robert Fishman, usually called Fish, is the central character in the 2008 comedy film The Rocker, played by Rainn Wilson.

Fish is introduced as the former drummer of the fictional 1980s hair-metal band Vesuvius. Just as the group is about to get a major touring opportunity, its members replace him with the record-company president’s nephew. Twenty years later, Fish is working an ordinary office job and has largely abandoned his dream of becoming a professional musician.

His nephew Matt eventually gives him another chance to play drums when Matt’s teenage band, A.D.D., needs a drummer. Fish’s return to music drives the film’s comedy and its underdog story. The nickname is also part of the character’s full name: Robert “Fish” Fishman.

The movie’s title refers to Fish’s identity as a rock musician, not to a band called The Rocker. Another easy mix-up is confusing Fish with the band Vesuvius: Fish was the drummer who was pushed out, while Vesuvius continued to enjoy success without him.