Using special effects to de-age actors is a risky proposition, but for Billy Crystal and Judith Light in their new series Before, the effort was worth it.

Premiering Friday, October 25, the Apple TV+ supernatural drama follows Eli (Crystal), a child psychologist who loses his wife Lynn (Light) and meets Noah (Jacobi Jupe), a “troubled young boy” with a “secret connection “. ” to Eli’s past, according to the synopsis. As Eli navigates the “mysterious bond” he shares with Noah, he also revisits moments from his decades-long relationship with Lynn.

Instead of casting younger actors to play Crystal, 76, and Light, 75, during flashback scenes, Before used aging technology on both actors.

“They did a test on him (Billy), and they first showed me this, and I said, ‘Billy, is this going to work?'” Light tells PEOPLE. “Because we were friends before, and I thought, ‘Honey, what are we.’ do?’ … We didn’t want to get younger actors because that often throws people out. It’s like, ‘Wait a minute. What is this? And we didn’t want people to be thrown out of the story at such a colorful moment when they first meet each other, and you realize these people are soul mates.”

“He’s showing me this with just him, and I was totally blown away,” she continues, adding, “I saw the two of us together, and I thought, ‘This is really amazing.’ It’s really amazing.”

While Lynn has many dark moments on screen, Light explains that it wasn’t difficult to draw on her considerable skills as an actor to make those moments compelling.

“It wasn’t hard at all, and it wasn’t like I had to reach in and kind of pull something out and do what they often call substitutions when you’re acting from your own life,” she explains. “It was just when you believe it, and it’s real, and you have a partner that you’re working with, and they believe it, and it’s real, something magical happens. Something shifts. You’re not in your head when you think about it.”

By portraying Lynn, who the trailer suggests that one feels badLight was able to easily and comfortably explore his character’s complicated journey.

“What does it tell you that somebody’s not doing well? What’s going on? What’s going on with the body? What’s breaking down? It wasn’t difficult by any means, and Billy was so supportive and so incredible,” Light says.

While Light reflects fondly on the project — “It was the most collaborative experience,” she says — she’s proud of Crystal, in particular.

“It’s nothing he cannot do. … He did Mr. Saturday night (A new musical comedy) where he sings and does eight shows a week,” she says of his Broadway appearance in 2022. “And I know he’s done dramatic work before. … I don’t hold Billy as, ‘Oh, yeah, it is the comedy guy.’ He is this incredibly versatile artist who is my friend. I knew somewhere subject which he would bring to this.”

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Before premieres Friday, October 25 on Apple TV+.