This movie set the record for the most bullets fired in an American film.

Mira Sorvino took the role in the film at the behest of then-boyfriend Quentin Tarantino, who told her she had to work with Hong Kong legend Chow Yun-Fat.

Mira Sorvino speaks fluent Mandarin Chinese. Chow Yun-Fat is a Cantonese Chinese native speaker, but can also speak some Mandarin. Sorvino was able to help translate for Chow, who was just learning English at the time.

During production, Columbia Pictures felt that Antoine Fuqua was struggling to deliver suitable material, and ordered a studio executive to be present during most of the filming to ensure that their money was being well spent. This angered Fuqua, and made things tense between him and Columbia. Debra Hill, a veteran producer, was called in by Columbia to cool things down. Chow Yun-Fat stood by Fuqua the whole time, and told the producers to trust him and his vision. The troubles didn't end after the production wrapped. When Fuqua delivered his initial cut, Columbia began testing the film. Test audiences struggled with the notion of a less-than-pure hero, and the bi-racial relationship between Chow Yun-Fat and Mira Sorvino. They also had issues with most of the other characters' backstories, so Columbia called in action editor Richard Francis Bruce to tighten up the film. All romantic elements between Chow and Sorvino were removed, along with most of the characters' motivations.

The Chinese character engraved on Lee's bullets means "death".

Chow Yun-Fat's first American film.

Also the first American film for Til Schweiger, who already was a major movie star in his native Germany at the time. Number of words his character, one of the title's replacement killers, speaks: zero.

Fuqua and Chow decided to cut some of the dialogue originally written for his role, partly to focus more on the visual aspects of the film, and partly because Chow's English wasn't that good back then.

Initially set up at Columbia as a starring vehicle for Chazz Palminteri. The Chinese mafia element in the original script was actually the more conventional Italian mafia.

When Antoine Fuqua and Chow Yun-Fat had the first meetings about the film, they talked about everything but the film. Also, Fuqua describes Chow as a quiet and peaceful man.

In the music that plays over the introduction of the "replacement killers" as they walk through the airport terminal, the female voice that is heard singing, is Claire Trevor singing "Moanin' Low" from Key Largo (1948).

Actually, Chow Yun Fat and Kenneth Tsang Work together 4 Films. A Better Tomorrow 1 and 2 The Killer and 1991 Once a Thief.

Danny Trejo Danny Trejo's character speaks only 4 words in the movie... "What about me?" and "Checkmate".

Chow yun fat and kenneth tsang starred together also in a better tomorrow 1986, a better tomorrow 2, and the killer

Chow Yun-Fat and Randall Duk Kim would work together again in Anna and the King (1999) and Dragonball Evolution (2009).