Jackie Chan has opened up to PEOPLE about the moment that changed everything. His father, Charles, revealed a shocking secret that left the actor stunned.

The Shocking Revelation

Chan, 71, recalled the moment his father "turned to him in the car" when he was "forty-something" years old and said, "I have a secret to tell you."

"My father suddenly said, 'Son, I'm old. I might sleep and never wake up'," the Rush Hour star recently told PEOPLE while promoting his newest movie, Karate Kid: Legends.

A Spy in the Family

"My father was a spy," the actor adds, adding that he was "very shocked" at the revelation and initially felt unable to listen to his father Charles' explanation of his past. "Then, later on, five hours later, I said, okay. Now I'm ready," Chan notes.

Chan commissioned the 2003 documentary Traces of the Dragon: Jackie Chan and His Lost Family, which tells the story of how his father worked as a government spy during the Chinese Civil War in the 1940s. His mother, Lee-lee, also had a secret past as an opium smuggler and gambler, which the film covered.

A Troubled Childhood

Chan also recalls to PEOPLE how Charles, who passed away in 2008 at the age of 93, and Lee-lee, a cook who died in 2002 at the age of 86, sent him away to a martial arts school because they were unable to control him.

"[As a child, I was] very naughty. Very naughty, I never go to school. All the books in my backpack? I always throw them away," he says with a laugh, adding that he learned "all kinds of skills" at the institution.

Road to Success

After being scouted at school, he became a stuntman in his teens and twenties before working as a stunt coordinator, actor, and director in Asia.

In 1995, Hollywood came calling with a role in Rumble in the Bronx, but it was 1998's buddy cop comedy Rush Hour opposite Chris Tucker that cemented his status as a star.

However, Chan, who has been married to former actress Joan Lin for 43 years, didn't initially understand the movie's humor. "Whatever Chris says, I don't understand. The culture is totally different," he explains to PEOPLE. Audiences disagreed, however, and the movie was a $244 million worldwide hit.

Returning to Karate Kid

As for returning to the Karate Kid franchise, Chan, who starred in 2010's The Karate Kid with Jaden Smith, says it means a lot to him. "[It's a] memory…not just a movie," he says with a smile.

"It's just unbelievable," he adds of acting alongside Ralph Macchio and Joshua Jackson. "Not only can I use my [martial arts] technique, I can show the Chinese culture to the world."

Karate Kid: Legends is now playing in theaters everywhere.

Read more about Ralph Macchio's age in each Karate Kid and Cobra Kai season and Joshua Jackson's reflection on his childhood dream come true role in Karate Kid Legends.

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