The film follows Hitman with a Heart John Lee, played by Chow Yun-fat in his first major Hollywood role, as he seeks to clear a debt with ruthless Triad crimelord Terence Wei (played by Kenneth Tsang) by killing his enemies. Unfortunately, the last contract is one that Lee cannot go through with — killing a cop's young son in revenge for the death of Wei's own son, a Triad lieutenant, in a police shootout.
Wei is pissed that Lee could not complete the contract, and not only seeks to kill him, but hires replacement killers in order to finish the job that Lee could not. Worse, he also has his men in China start looking for Lee's family to take revenge upon them as well. Lee seeks to ensure his family's safety by having them moved to a secure location, and for this purpose enlists the help of skilled forger Meg Coburn (Mira Sorvino) to create a new passport for him. The two soon have to deal with not only the assassins sent to kill Lee, but the replacement killers sent to kill the cop and his son, as well as finding a way to stop Wei from exacting horrible vengeance against Lee's family.
This film provides examples of:
- Action Girl: Meg. Possibly a Dark Action Girl, given her career choice.
- Action Prologue: John's hit at the nightclub, followed by Zedkov's attempted drug bust of Wei's son.
- And Your Little Dog, Too!: Wei's standard method of getting even with his enemies: kill their families and anybody else they hold dear and leave them suffering (and maybe kill them after they have wallowed for a while).
- Antagonist Title: The titular "replacement killers" are the hitmen hired by Terence Wei after John refuses to finish his contract.
- Artistic License – Religion: In one scene, John berates the temple's Buddha statue for bringing unfair misfortune on his family, in all probability because the scriptwriter was under the impression that all religions work just like Christianity and their respective icon of worship must be the culprit and target of any Rage Against the Heavens. In reality, John's action makes absolutely no sense: Buddha is not the equivalent of God and isn't supposed to have any kind of control over the things that happen in the world, either good or bad, which instead obey to an impersonal principle of the universe named karma (and not even all of them, as Buddha stated that many events are not brought by previous karma and instead happen, you know, because they can happen).
- Back-to-Back Badasses: Meg and John during the shootout at her office, sort of—they face opposite directions to take out each other's would-be shooter.
- Badass in a Nice Suit: John, at the beginning.
- Badass Longcoat: Ryker, the big, German-looking replacement killer.
- Best Served Cold: Wei wants to be sure Zedkov's son dies in his arms so Zedkov will understand Wei's pain.
- Big Bad: Terence Wei.
- Briefcase Blaster: Ryker is equipped with this. (Since he and Collins carry out their assignment like proverbial bulls in a china shop, one wonders why he bothers disguising his weapon.)
- Bullying a Dragon: A handcuffed and helpless Meg decides it'd be a good idea to mock one goon that she'd earlier shot in the leg. This goes as poorly for her as you'd think:Meg: "How's the knee?"*Mook kicks her in the knee and dislocates it*Mook: "...How's yours?"
- Butt-Monkey: Loco.
- Car Fu: Meg uses this in the final battle, although it's more Van Fu.
- Carnival of Killers: John Lee is being chased by a group of assassins that are vying for his position, after he refused to perform a hit on the cop who killed his former employer's son, while Lee attempts to get back to China to save his family from the vengeance of the mob boss.
- Catchphrase: Meg's "I didn't think so."
- *Click* Hello: John pulls this on Collins right before he kills him
- Contract on the Hitman: John's former boss offers a contract to several assassins for killing John.
- Cool Shades: John, occasionally, and a few of Wei's men.
- Damsel out of Distress: John's hostage holds her own against the bad guys.
- Deliberately Bad Example: The titular "replacement killers" to John. Not only are they perfectly willing to kill a kid as long as they paid, but while John is clean with his hits and only kills those he's been paid to kill, they just unleash More Dakka and kill those they've been paid to kill, anybody unlucky enough to stand in the general vicinity, and any law enforcement that tries to stop them.
- Disney Villain Death: Wei.
- The Dragon: Michael Kogan.
- The Dreaded: John has shades of this by the end. When John stands in front of Wei's limousine, rather than trying to run over John, the driver immediately starts backing away as fast as possible while his passengers cower in the back. Said passengers include the boss of a massive criminal empire who is abandoning his headquarters (and possibly city) just to get away from John.
- Even Evil Has Standards: Subverted. John isn't evil—he's being forced to do Wei's bidding.
- Fanservice: Meg is caught getting dressed early in the film and has to run away with John. She spends most of the movie with only one button, apparently not having the time to dress all the way.
- Fire-Forged Friends: By the end of the movie, it's obvious that they have become close friends after all they have went through together.
- Gangsta Style: Hilariously inverted. With John and Meg in a Mexican Standoff against a over a dozen gangsters, most of them are holding their guns properly (though a few are Gangsta Style), but the professional assassin is holding his single pistol sideways the entire time.
- Graceful Loser: Collins, before being shot in the head from behind by John, simply smiles and utters, "Checkmate."
- Gun Fu
- Guns Akimbo: Of course.
- Heroic Bloodshed
- Hitman with a Heart: John. The man has no problem commingling murder for hire, but killing an innocent kid is beyond him.
- His Name Really Is "Barkeep": When John first arrives to Meg's office looking for a counterfeit passport to go back to China, he says the name he wants for the passport is "John Lee", which Meg says is the fakest name she's ever heard for a false identity. Then she meets Alan, and he tells her that John's name is "John Lee".
- Honor Before Reason: Not only does Lee seek to ensure his family's safety, but also to keep the cop and his son from getting killed by Wei's replacement killers.
- Imperial Stormtrooper Marksmanship Academy: Where the replacement killers evidently learned their trade.
- Informed Ability: See above entry. For professionals, the movie's title characters really suck at their job. Wei could have saved a bundle by just hiring a few idiot gangbangers to haphazardly spray bullets in Lee's general vicinity and cause shitloads of collateral damage in the same way our "elite" replacement assassins repeatedly do.
- It's Personal: For everybody except Meg, who's just sort of dragged into the situation. Although, before the final fight she insists on coming along because she now cares what happens to John.
- Kirk Summation: "So you didn't want to shoot a kid; Welcome to the human race."
- Leap and Fire: Lee performs many different maneuvers while fighting to survive, including this one.
- Marked Bullet: John's calling card. If he sets one on the table in front of you, kiss your ass goodbye.
- Mexican Standoff: An epic one involving John and Meg when they visit Loco.
- Between John and Wei at the end.
- Ms. Fanservice: Meg spends most of the film only dressed halfway. In a very brief scene, she is seen striping down to her bra and panties.
- Nothing Personal: Loco basically says this after he gave away the location of Meg and John to Wei's men, claiming they were marked and he would be causing himself "unnecessary drama" if he didn't make the call after being seen with them.
- One Last Job: What John's assignment to kill Zedkov's son was supposed to be.
- One Bullet Left: John's last bullet in the final fight is his Marked Bullet. He uses it on Wei with a nice Pre-Mortem One-Liner.
- Outlaw Couple: One is a hitman and the other works as an illegal forger. And yet, they back each other up and fight as if they have fought along time before.
- Pre-Mortem One-Liner:Wei: "The boy will die, John. And so will your family".
John: "Not on your lifetime." (Wei is Blown Across the Room). - Red Oni, Blue Oni: John is blue, Meg is red.
- Revenge by Proxy: Not only does Wei want Zedkov's son to die in revenge for his own son's death, but when Lee proves unable to go through with it, he seeks to kill not only Lee, but his family as well. He's a bastard like that.
- Sacrificial Lamb: Wei's son winds up being this, kicking off the revenge plan.
- Shameless Fanservice Girl: Meg shows signs of this in the film. She starts off wearing a thin black dress that’s unzipped in the back, showing her full back and bra. She changes out it for something slightly more modest but has her shirt unbuttoned showing her bra. By the end of the movie, she dresses up much more modest and looks cleaner.
- The Triads and the Tongs: The major bad guys in this flick.
- Throw-Away Guns: Most apparent in the final battle-John spends most of it performing "New York Reloads" and carrying on blasting.
- Would Hurt a Child: Wei and the replacement killers, in direct contrast to Lee.
- Wouldn't Hurt a Child: Leads to John's inability to complete his assignment.
