Bruce Lee had a rich and storied friendship — and rivalry — with fellow big screen icon Steve McQueen. Both Lee and McQueen were two of the biggest actors of their era, but they also hailed from two different worlds. Lee was a rising star in the martial arts movie industry, while McQueen was an A-list actor in Hollywood and a household name.

Today, Bruce Lee is remembered as a martial arts legend who wowed audiences with his performances in five kung fu movies, one of which being the Hollywood classic, Enter the Dragon. However, it took him a while to gain this reputation, whereas his friend, Steve McQueen, had been making movies in Hollywood for several years and was high-in-demand by some of the biggest studios in the industry. During the 1960s, McQueen starred in big movies like The Magnificent Seven, Bullitt, The Thomas Crown Affair, and The Great Escape. He also received critical acclaim for his role in the anti-Vietnam War film, The Sand Pebbles, which earned him an Oscar nomination for Best Actor.

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Sometime after the cancellation of The Green Hornet in 1967 and long before his breakout role in 1971’s The Big Boss, Bruce Lee was out of work; he befriended McQueen, who was ten years his senior and already incredibly famous. They met through their mutual friendship with celebrity hairstylist Jay Sebring. Their association began with McQueen hiring Lee to teach him kung fu. The two didn’t become fast friends, as McQueen biographer Marshall Terrill has noted that the actor was “too paranoid” to make friends with people easily, so his friendship with Lee had to grow from the time they spent training together. At first, McQueen spent time with Lee because he felt that that he had something he could learn from the martial artist. During their training sessions, Lee was greatly impressed with McQueen, a person who he said “doesn’t know the meaning of quitting.

As their bond deepened and the respect that they had for each other grew stronger over time, the two formed what Terrill called a “professional sibling rivalry.” Lee’s goal was always to become a huge star in Hollywood, and he wasn’t shy about his intention to become even more famous than McQueen himself. His ambition to surpass McQueen increased when Lee and James Coburn began developing The Silent Flute. It was Lee’s plan for McQueen to star in the movie, but he refused to take the part, explaining that he didn’t want to use his fame to “make other people stars” [via Closer Weekly].

As furious as this made Lee, they remained friends. One popular story about their friendship involves them going for a drive, and Lee being terrified by McQueen’s ridiculously fast driving. Their bond survived that and more, as did their rivalry. After making a few movies, Lee wrote a letter to McQueen, claiming that he was now the bigger star. McQueen humorously responded with a photo of himself signed, “To Bruce, my biggest fan”. Following Bruce Lee’s death, the strength of their relationship was demonstrated when McQueen served as a pallbearer at the actor’s funeral.

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