NOTE: This spoiler sent in by Rudy's Mom.The movie begins with the police going to the house of George Reeves (Ben Affleck), the former Superman. He has been shot the night before in an upstairs bedroom, in an apparent suicide. The guests downstairs - his girlfriend Leonore and their 2 guests are just sitting around.
The next scene is at an apartment where private detective Louis Simo (Adrien Brody) lives. He is fooling around with his secretary. A male client comes in, and wants Louis to follow his wife, who he believes is cheating. Louis thinks the wife probably is not cheating since he has followed her before with no results. But he agrees and takes the money.
The next scene is at a coffee shop. Louis meets with a policeman and asks if he knows of any interesting cases he can work on. The policeman suggests that Louis speak with the mother of George Reeves, because she is looking to hire someone to investigate her son's death. The police think it is suicide, but she disputes that.
Louis goes to visit his ex-wife and son, who is about age 10. The son is distraught that Superman killed himself. Louis then visits the mother and she hires him. Louis goes to the morgue, and sees the body. The body has bruises on the hands, and Louis wonders if someone worked Reeves over before killing him.
There are some flashbacks of Reeves when he first meets Toni Mannix (Diane Lane) at a party. At that point, Reeves is a minor actor whose only notable role was a small part in Gone With The Wind. She is the wife of a powerful studio executive, Eddie Mannix. They sleep together. She explains that she and Eddie have an open marriage. She assures him that her husband won't hurt his career to retaliate for the affair. In fact, there is a hilarious scene of the four of them having dinner together: Reeves, Toni, Eddie, and Eddie's mistress.
Toni arranges for Reeves to interview for Superman. Eventually the Superman show becomes a TV show, and Reeves becomes famous to children. Over time, Reeves and Toni have a long-term affair apparently spanning several years.
In the flashbacks, Reeves eventually breaks up with Toni and gets a new girlfriend, Leonore (Robin Tunney). Toni is upset and jealous. Toni drives by Reeves' house and spies on them. Leonore is portrayed as a cheap woman with no class or taste. Reeves says that he likes her because she makes him feel young.
In a subplot, the husband that hired Louis at the beginning of the movie shoots his wife in an act of jealous rage. Louis' personal life is also suffering. His tells his secretary girlfriend to leave him, as he knows that she is cheating on him.
Louis takes the mother to visit the house where Reeves shot himself. He notices that there were 2 bullet holes in the floor. He wonders whether someone took 2 shots at Reeves before shooting him. Leonore says that she fired those shots herself by accident.
One night Louis checks the house, when no one is supposed to be there. He finds Leonore there, also. She is looking for travelers checks that she left in the dresser. She denies killing Reeves.
Louis' investigation seems to focus in on Toni Mannix and her husband Eddie (Bob Hoskins). There are flashbacks where Toni is very distraught at Reeves breaking up with her, and Eddie is upset with Reeves for hurting his wife. Louis sneaks in to the Mannix house and confronts Eddie. Eddie has his henchmen beat up Louis.
The movie closes with the last evening of Reeves life. Reeves is at his house with Leonore, and the 2 friends. He plays guitar and looks happy. Then he walks upstairs. The movie suggests that there are several possibilities: The killer could be Toni or Eddie, or it could be suicide.
We'll never know.