In 1985, Jackie Chan grabbed an umbrella and ran towards a moving bus. Here’s how Police Story changed action cinema forever.

There had never been an action scene quite like the one that appeared in the first few minutes of 1985’s Police Story. Jackie Chan’s plucky cop, in dogged pursuit of crime boss Chu Tao (Chor Yuen) engages in a wildly destructive car chase through a hillside shanty town, demolishing rickety buildings and detonating gas bottles in his wake. When Tao and his goons then make their escape on a stolen bus, Chan’s Sergeant Kevin hooks onto the back with the help of an umbrella, his body flung to and fro as the vehicle lumbers through traffic.

The scene is brilliant not just because Chan’s risking his neck by doing his own stunts. It’s not just brilliant on a technical level (the planning that went into...