Martial arts star Bruce Lee was born in San Francisco in 1940, but spent much of his childhood in Hong Kong and made his movie debut there while still a baby—alongside his father, Lee Hoi-chuen, who was a famous opera star in China. Bruce Lee secured his first lead role while still a child too, starring in 1950’s The Kid when he was just 9 years old.

And it was around that time that he first began learning martial arts, continuing his studies even after returning to America to take drama at the University of Washington in 1959.

Eventually, however, Lee abandoned his college career to focus on martial arts full-time, and in the mid-1960s landed the role of Kato, the high-kicking valet and sidekick of Van Williams’ eponymous Green Hornet, in a new ABC series.

Although the series was short-lived, its success would later pave the way for Lee’s iconic roles in movies like Fist of Fury and Way of the Dragon—but long before then, he and Williams made a memorable crossover into another of the 60s most iconic series.

ABC was also the network responsible for the original Batman series starring Adam West, and Burt Ward as Batman’s plucky young sidekick, Robin. An episode of Batman was ultimately conceived in which the four characters would meet up and together save Gotham City from another dastardly supervillain—but there was a problem.

The script had it that when the four characters met for the very first time, they initially believed one another to be the villains, and began fighting. And, as it was their series that the episode was a part of, Batman and Robin were supposed to prove victorious, defeating the Green Hornet and Kato, before realizing that they were all on the same side. Lee, however, was not happy.

According to Williams, Lee refused to shoot the scene, claiming that viewers would know full well that he would never lose a fight against Burt Ward’s Boy Wonder. Williams, for his part, agreed—as too did Adam West and Burt Ward (who was reportedly less than keen to enter into even a staged fight with a performer as skilled as Lee).

With the episode at a standstill, the entire scene was rapidly rewritten: the fight remained, but ended inconclusively, with Batman and Robin working out much earlier than had previously been intended that their opponents were in fact their friends. Lee agreed to the compromise and ultimately was able to remain undefeated on the small screen.