Bruce Lee had to beat out James Tien for the lead role in The Big Boss. Released in 1971, the Hong Kong film was Lee’s first kung fu movie. The huge box office hit was largely responsible for Lee’s transformation into a martial arts superstar. Directed by Lo Wei and produced by Hong Kong studio Golden Harvest, The Big Boss starred Bruce Lee as Cheng Chao-an, a person who swore to his late mother that he wouldn’t partake in any fighting.

This promise was put to the test when he went to stay with his cousins, who worked at an ice factory. One of them was Hsu Chien (James Tien), a highly skilled martial artist. While there, Cheng found himself embroiled in a battle with gangsters who were using the factory for their drug smuggling operations. When he found out that they were the reason why some of his cousins (including Hsu Chien) were mysteriously disappearing, he had no choice but to break his vow and fight the villains.

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Lee’s character being the hero of The Big Boss wasn’t actually how the story was supposed to go. Originally, the lead role belonged to James Tien, an actor who already had a career in martial movies at Shaw Brothers Studios. Golden Harvest’s plan for the film started to change a bit when they signed a contract with Lee, having been impressed with his work in The Green Hornet (1966). He was subsequently cast as one of the characters The Big Boss, but not as the lead. When Lee clashed with director Wu Chia-Hsiang over the martial arts choreography, Golden Harvest replaced the director with Lo Wei, who leaned toward making Lee the new star.

Even while filming was still underway, which actor would end up playing the main character remained up in the air. To help reach a decision, Lo had Tien and Lee alternate days when shooting their respective fight scenes. The fact that the script was only three pages long gave Lo a lot of leeway when it came to planning the film. Though he didn’t get along well with Lee, Lo still found himself more pleased with Lee’s performance than Tien’s. He eventually reached the conclusion that Lee was the best choice to play the main protagonist. As a result, they made some adjustments and killed off Tien’s Hsu Chien, which explains why he vanished from the story early on. He became one of the missing cousins that Lee’s hero had to investigate.

Needless to say, the move proved to be a good one, as Lee became Golden Harvest’s top star after The Big Boss. As for James Tien, he of course didn’t encounter the success that Lee did. He was mostly cast in supporting roles after that, one of which was in Lee’s second martial arts film, Fist of Fury. He also appeared in dozens of lesser-known kung fu movies for Golden Harvest through the 1970s and '80s, with many of them being Jackie Chan vehicles.

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