Big time baseball star Bobby Rayburn (Wesley Snipes) signs a $40 Million dollar contract with the San Francisco Giants, who is the favorite player of knife salesman Gil Renard (Robert De Niro). Gil is a very obsessive, compulsive fan who cares more about the game than his job and this problem causes him to neglect his son among other aspects of his life. Gil takes his son to see Rayburn and the Giants opening day game where he lashes out at other fans and his son for not having the same "passion" he does for the game. During the game Gil leaves his son to watch the game while he races to a meeting only to find out the man he's meeting is at the game. When Gil returns to the ballpark his son is gone. Gil goes to his ex-wifes house bargaining through the door to find his son was brought home by a concerned woman. He locks himself in his sons bedroom and is determined to make sure his son plays baseball and becomes a great player someday. After Gil leaves he is served with a restraining order to stay away from his son. Around the same time Gil is fired from his job for not selling enough knives causing him to become more violent and obsessed.
Rayburn starts off strong with a grand slam in the opening game, but soon starts to fall into a major slump and the Giants fan base turns on him. Gil blames Juan Primo (Benicio Del Toro) for not allowing Rayburn to have his lucky number. After a confrontation with Primo to try to convince him to give Rayburn the number, Gil murders Primo while at the sauna. After Primo's murder, Rayburn starts playing good again and Gil believes its because he killed Primo. While Gil is stalking Rayburn at his beach home one day, Rayburn's son almost drowns but Gil jumps in and saves him. Rayburn thanks him and invites him in for clothes and a drink. Gil dresses up in all of Rayburn's field gear and asks Rayburn to let him throw him a few pitches which they do, but as the continue talking Gil becomes enraged when Rayburn refuses to say that he's glad Primo is dead. After Rayburn leaves, Gil kidnaps Bobby's son and takes his car and dog as well. Holding Rayburns son hostage, Gil tells Bobby that if he wants to see his son again, then he is to hit a home run for him at the next game and dedicate it to Gil " A True Fan". Rayburn struggles all game, but at his last time up to bat, he hits a in the park home run. As Rayburn slides in to home base, the umpire calls him out.
Frantic, Rayburn starts to argue with him until he realizes it is Gil. Gil stabs a player before directing his knife towards Rayburn. Gil tells him he wants to show him his best pitch using the knife, but before he can throw it, the police shoot him down killing him. Thanks to a hint from Gil's son, they are able to find where Gil was keeping Rayburn's son and they are reunited.
Thanks Eric D!