Michael Keaton Reveals 'Intelligent' Jack Nicholson Flew Him to Paris in a Jet: He 'Didn’t Leave His Room' Until After 10 P.M.

Michael Keaton exposed Jack Nicholson 's party boy ways!

Keaton and Nicholson, who appeared together in Batman , immediately connected.

“I just really liked him,” Keaton, 73, who is still in touch with the actor , 87, told People in a new interview. “He's really, really intelligent. Really. A real reader. Just has an innate intelligence, and then a self-taught intelligence. ... Because he devours books. Always something to talk about. Very opinionated about things when you're in a conversation."

He went on to recall the time they went to the City of Light together. “He took me to Paris in a jet,” recalled Keaton. “I was like a Boy Scout. I was ready to go out like a normal person. Jack didn’t get out of his room until like 10 p.m. or 10:30.”

The A-listers ended up venturing to the exclusive Les Bains Douches nightclub. “Jack was having a ball. He had the biggest grin on his face,” Keaton, who went back to the hotel before his costar, said.

He recalled thinking: “‘This is fun, but it’s kind of wasted on me.’”

Meanwhile, Nicholson has been keeping a low profile over the past few years .

According to director James L. Brooks , he wants to bring Nicholson back to showbiz again.

“I keep on thinking he's going to get itchy and scratch it,” Brooks previously said.

Nicholson previously appeared in How Do You Know — but Brooks doesn't think this is the end for him. “My theory is it’s not his last movie.”

“That’s what I’m hoping for. He’s the man," Brooks said, hoping that Nicholson has interest in acting going forward .

Never miss a story — sign up for the OK! newsletter to stay up-to-date on the best of what OK! has to offer. It’s gossip too good to wait for!

Though Brooks hopes Nicholson will return to work, it doesn't sound like that will be happening anytime soon .

"A friend of mine wanted to put him in a movie. And he had a conversation with him. But Jack says, 'I don't want to do it.' He goes, 'You know what I did today? I sat under a tree and I read a book,'" Nicholson's pal producer Lou Adler said on a recent episode of "WTF with Marc Maron."