Suckerfish (1999)

Comedy about the wholesale pet supply business finds two veteran salesman trying to squeeze out a new kid hired to take over a retiring pro's lucrative route. Initially naive, the kid doesn't understand why his sales are drying up. What he doesn't know is that the other two are spreading vicious rumors about him including that he practices his golf swings on pet rodents and other absurdities. Eventually though, he becomes wise to their schemes and decides to fight back. Armed with the knowledge that Donovan is having an affair with Orr's wife, he sets off on revenge.