The movie begins with professional tennis player Aaron Faust (Sharples) playing an exhibition match at the estate of the late Mickey Rooney.

Despite the fact that the match is for a good cause "benefitting underprivileged children," Aaron has a John McEnroe-like meltdown over a line call then punches his opponent who finds Faust's Achilles heel when he taunts him for playing a “pussy sport.” Banned from the ATP tour, dumped by his fiancé, and sentenced to anger management, Aaron is blindsided by the sudden turn his life has taken and laments that "tennis is missing something" but doesn't quite know what it is.

Though hesitant at first, Aaron is excited to learn that Gentlemen's Fury is made up of other former pros who were excused from the tour for questionable behavior and that the league takes significant liberties with the rules of tennis, essentially turning it into a contact sport, so he joins the squad.

Dwayne, in true cult leader fashion, transforms from a guy spouting a new tennis utopia into a crazed psychopath with more than one homicide on his hands, while Aaron struggles at first to keep up, then just to survive.

Gentlemen's Fury makes tongue in cheek references to several actual ATP players who had infamous incidents that resulted in their suspension from the sport, including McEnroe, Bernard Tomic, Nikolai Davydenko, Jeff Tarango, Wayne Odesnik, and Richard Gasquet.