In this movie, Bruce Lee's character is shot with a prop gun that was secretly made to fire a real bullet and kill him. Lee's son, Brandon Lee, was killed on the set of The Crow (1994), when a prop pistol accidentally shot him in the abdomen.
Bruce Lee had filmed over 30 minutes of fight scenes for this film when work was suspended to allow Lee to work on Enter the Dragon (1973). However, Lee died before he could return. Six years later, director Robert Clouse fleshed out a feature around the original footage with a new cast, including two stand-ins for Lee, who faces are hidden by dark sunglasses and shadows. Close-ups and stills of Lee's face, including a cardboard cut-out, were also used.
George Lazenby was originally meant to be in this film and was due to meet Bruce Lee on July 20 1973, the day Lee died. For other reasons, Lazenby was not involved in the final project as directed by Robert Clouse.
Sammo Kam-Bo Hung almost didn't appear in the film. When Bruce Lee personally asked him to be part of the film, Hung waited for eight months without follow-up and eventually went to film projects in Korea and Thailand. He flew back to the set in China when promised that filming his part would only take a few days.
In Bruce Lee's original story plot, he was to play a world renowned martial artist named Hai Tien. Tien was to be approached by the Korean underworld and told about a mysterious treasure at the top of a pagoda. Hai Tien would want nothing to do with it, but when his sister and younger brother are kidnapped Hair is forced to co-operate. Although the name Hai Tien came up at least once in the archive footage, Robert Clouse and co. Changed his name to Billy Lo.
The inspiration for progressively ascending a pagoda tower to fight opponents was originally featured in Cheh Chang's swordplay epic Bao biao (1969) written by resident Shaw Brother screenwriter Kuang Ni.
The trivia items below may give away important plot points.
The Chinese version of the film features a complete extra fight scene: Billy Lo vs a Korean challenger (played by legendary Tae Kwon Do master Casanova Wong). This fight was later inserted into Game of Death II (1981). This is considered by far the best "non Bruce Lee" fight scene in the whole film.
The movie has three different endings. The US/international version cuts to the credits montage right after Dr. Land falls to his death. In the Cantonese version, the police arrest Billy Lo after Dr. Land dies (a Hong Kong movie requirement at the time). In the Mandarin version, Billy Lo escapes on a boat with Ann Morris. The Cantonese and Mandarin versions also have completely different end credits and music.