Half Fast
Touchdown! Greaser!
In Terminator 2, Schwarzenegger said, "I'll be Back." Rather famous line. The actors are all saying that they'll be various classical composers. One famous composed is named Bach. Thus, the joke is that they're trying to get him to say his famous line and he's refusing.
Maybe instead they could make a movie about magazine publisher immigrants who became wealthy philanthropists, so they could trick him into saying “I’ll be Bok.”