Rick Santoro (Cage) is a corrupt police detective, serving in Atlantic City, New Jersey. He has been bullying people and accepting payoffs for years. One day, Rick attends a heavyweight championship boxing match. Also in attendance is Charles Kirkland (Joel Fabiani), the United States Secretary of Defense. Among those escorting Kirkland is Kevin Dunne (Gary Sinise), a Navy Commander and close personal friend of Santoro. During the match Julia Costello (Carla Gugino) attempts to approach Kirkland. Sudden gunshots wound Costello and kill Kirkland. Havoc ensues throughout the arena as the fight is stopped and fans stampede toward the exits.
Rick is at first determined to track Julia, considering her a suspect. He soon realizes however that Kirkland was killed due to an unpopular decision of his, canceling a missile defense project. Certain elements of the military forces felt the project was necessary. The corporation hired to create the project wasn't happy either. Rick finds himself facing a conspiracy, with the conspirators being far more ruthless than him.
This film provides examples of:
- Acoustic License: Rick somehow not only hears his cellphone ring while sitting in the front row of a crowded sports arena during a boxing match, but then has a conversation on it with no problem.
- Better to Die than Be Killed: At the end of the movie, the Big Bad shoots himself rather than be taken alive or shot by the police.
- Big Bad Friend: The best friend of Rick Santoro turns out to be a Well-Intentioned Extremist with blood on his hands.
- Bittersweet Ending: Rick Santoro solves the conspiracy, most of the conspirators - including the mastermind - wind up dead, and he even gets the girl. But the media uncovers his corruption and he's set to do jail time at the end, but only for a couple of years.
- Chekhov's Gun: Subverted. There is a huge ball that has been lying on the ground for most of the movie. Almost inviting you to believe that is plot relevant and will eventually roll over someone. It doesn't. However, this was only because test audiences didn't like the originally-planned ending in which it does roll over the main villain.
- The Conspiracy: "Five people make a conspiracy, right?".
- Conspiracy Thriller: A very stylized one, too.
- Covers Always Lie: Rick Santoro spends the entire movie in a beige colored jacket, but the cover has him wear a purple jacket.
- Dirty Cop: The boisterous protagonist Rick Santoro is an arrogant, corrupt detective who sees Atlantic City as his own Wretched Hive. He takes bribes, doesn't hesitate to use Police Brutality, and sleeps around on his wife. The conspirators even get him involved because they knew he could be bought if he found out too much. He draws the line at plain murder, though.
- Distracted by the Sexy / Show Some Leg:
Dunne: I was three feet away from a known terrorist, and I had my eyes buried in some broad's tits.Santoro: Well, Kevin, this might not make you feel better, but don't you see? That's what she was there for, that was the plan. To give you a boner. And you got one! Congratulations, you're human.
- An attractive woman is planted in the crowd to get Dunne out of the way for the assassination.
- Subverted in the end. She was in on it with Dunne.
- Focus Group Ending: Before the focus groups got their hands (er, eyes) on it, De Palma had a chase through a flooded tunnel and the bad guy getting run over by a globe which has been lying on the ground since the start of the movie. When it came to theaters, the chase doesn't go through a flooded tunnel (thus at odds with Nic Cage's reference to it in the epilogue), the globe gets washed off by a wave, and the bad guy kills himself.
- Fiery Redhead: Serena played by Jayne Heitmeyer.
- Irony: Nick accepts a five thousand dollar bribe from a low-level reporter who wants to do the exclusive on the scene coverage of the assassination, so he can get his big break. During the ending, that same reporter is one of many covering Nick's fall from grace, once his corrupt history is made public to the mainstream media.
- Large Ham: Nicolas Cage, unsurprisingly.
- Lucky Seven: Referenced by Santoro when he sees the Pit Girl holding the sign for the 7th round in the boxing fight. She later unwittingly distracts Santoro when the Secretary of Defense is assassinated at the match, so she's probably not a very good token.
- No Good Deed Goes Unpunished: Santoro is a sleazy corrupt cop who suddenly finds his conscience when he uncovers and subsequently tries to prevent a plot to assassinate a political whistleblower. He succeeds, and in the epilogue he is initially hailed as a hero, but winds up going to jail after the extra publicity shines a light on his shady past.
- The Oner: De Palma loves this trope and Snake Eyes is primarily known for this.
- Once More, with Clarity! The movie shows flashbacks from the perspective different people about the same scenes (or not) adding a little more context each time.
- Pit Girls: Rick Santoro (Nic Cage) flirts with one of these who's holding the card fo round #7 before the big fight. She calls him on his phone during a vital moment, unfortunately distracting him when the Secretary of Defense, who was seated near him, is assassinated by a sniper.
- Reality Ensues: The film ends with Nick, the Corrupt Cop main character, being praised by the media as a hero for stopping the assassination of a political whistleblower. However, after he becomes a national hero and a media darling, all the poorly hidden corruption in his life quickly come to the surface. Every criminal that he ever shook down or was a brutal Jerkass to is quick to try to bring him down by telling about Nick's corruption, all his Suspicious Spending is brought to public attention, etc. This all leads to him getting fired, divorced, and facing prison time. Turns out that it doesn't matter if you're considered a hero, having all your bad behavior brought to the surface can force the police and society to turn on your for all the things you've done.
- Take Me Out at the Ball Game: Charles Kirkland is assassinated in a high-profile Atlantic City boxing match.
- Throwing the Fight: Footage of the boxing fight does not only reveal details of the assassination but that one guy faked a knockout.
- Title Drop: Twice.
- "You've got nothing kiddo. Snake Eyes. The house wins."
- And later: "There's no "we", Kevin. You've got Snake Eyes."
- Turn Off the Camera: When the Secretary of Defense is assassinated at a major boxing event, photographers immediately swarm over the site. Detective Rick Santoro punches out one of them and tells the guards to get the rest removed from the crime scene.
- Unreliable Narrator: Out of the many flashbacks narrated in continuous first-person point of view shots, one is a pure invention by the narrator.
- Villain Has a Point: Kevin tells Nick step-by-step what would happen if he succeeded in playing the hero. How he would be praised at first, until they found out about his corrupt past. He was right.
- Villainous BSoD: After being caught in the middle of trying to kill Nick and complete the assassination of Julia, Kevin belatedly realizes how screwed he is; he can't pull rank with the local cops who have him dead to rights, he's caught on camera, and no one is left who will try to save him or corroborate his story. He more or less goes into shock and briefly becomes an empty shell of a man as he realizes that his entire life's work is crashing down around him and there's nothing he can do about it and no way out. His eyes even go blank and get a Thousand-Yard Stare. When he gradually comes back to himself and confirms there are no good options for him, he quickly commits suicide rather than live through the Humiliation Conga that will come next.
- Wig, Dress, Accent: Julia appears at the fight in a blonde wig and white dress when she attempts to talk to Kirkland.
- Well-Intentioned Extremist: Kevin's reason for why he got involved with the assassination of the Secretary of Defense: the Secretary was putting politics above the safety of American Sailors who once suffered heavy loses without the next-generation air defense missile technology the Secretary had cancelled.