Michael Keaton Teases Beetlejuice Sequel: A 'Shrunken Head Room' and 'Enormous Fun' (Exclusive)

The “ghost with the most” is sharing some secrets about the Beetlejuice sequel.

While promoting his new dramatic thriller Knox Goes Away, Michael Keaton, 72, tells PEOPLE about making Beetlejuice Beetlejuice, the long-awaited follow-up to the 1988 comedy about a rude and crude demon who’s enlisted by two ghosts (played by Alec Baldwin and Geena Davis) hoping to scare away the new owners of the home they once inhabited.

“It's the most fun I've had on set in a long time,” says Keaton, who filmed the movie last year with returning stars Catherine O’Hara and Winona Ryder, as well as cast additions Monica Bellucci and Jenna Ortega. Tim Burton returned to direct as well.

“On one hand, you'd go, ‘Well, of course it's the most fun. It looks like fun.’ As you know, it doesn't always work like that,” he continues.

Keaton says he and Burton, who have worked together on other films including Batman and Batman Returns, floated the idea of revisiting the movie at different times through the years.

“We thought, ‘You got to get this right. Otherwise, just don't do it. Let's just go on with our lives and do other things.’ So I was hesitant and cautious, and he was probably equally as hesitant and cautious over all these years,” he says.

“Once we got there, I said, ‘Okay, let's just go for it. Let's just see if we can do it, if we can pull this off,’” he adds.

Burton and Keaton agreed they didn’t want to turn the sequel into a CGI extravaganza.  

“The one thing that he and I decided on early, early, early on from the beginning, if we ever did it again, I was totally not interested in doing something where there was too much technology,” he says. “It had to feel handmade.”

“What made it fun was watching somebody in the corner actually holding something up for you, to watch everybody in the shrunken head room and say, ‘Those are people under there, operating these things, trying to get it right,’” he continues.

While Keaton did not elaborate on the shrunken head room, the first film featured a scene in which Beetlejuice’s own head gets shrunk by a witch doctor who also shrunk the head of a hunter.

“It's the most exciting thing,” says Keaton. “When you get to do that again after years of standing in front of a giant screen, pretending somebody's across the way from you, this is just enormous fun.”

O’Hara, who reprises her role as eccentric Delia Deetz, recently spoke with PEOPLE about her own experience making the movie. 

“I had a little two person moment with Michael as Beetlejuice. I'd been in the first movie in group scenes with Michael, but in this, I had an actual moment where the two of us just. And it was just so crazy and thrilling, really to just be face-to-face with Beetlejuice.”

“He looks the same,” she joked. “Beetlejuice has aged very well.”

Before Beetlejuice Beetlejuice hits theaters this September, Keaton is focused on his passion project Knox Goes Away: He directed and stars in the drama as a hit man who’s diagnosed with a rapidly-advancing form of dementia.

With just weeks to live, he tries to help his estranged son Miles (James Marsden), who’s murdered a white supremacist that took advantage of Miles’ teen daughter.

Knox Goes Away is in theaters March 15.