Judith Light Reveals Her Reaction to the De-Aging Process in Before: ‘Gobsmacked’ (Exclusive)

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.

The Apple TV+ supernatural drama, premiering Friday, Oct. 25, centers on Eli (Crystal), a child psychologist who loses his wife Lynn (Light) and meets Noah (Jacobi Jupe), a “troubled young boy” with a “haunting 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.

Rather than casting younger actors to play Crystal, 76, and Light, 75, during flashback scenes, Before used de-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 was like, ‘Honey, what are we doing?’ … We didn’t want to get younger actors because that often throws people. 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 climactic moment when they’re first meeting each other, and you realize that these people are soulmates.”

“He shows me this thing of just him, and I was completely gobsmacked,” she continues, adding, “I saw the two of us together, and I was like, ‘This is really astonishing. It’s really stunning.'”

While Lynn has many dark moments onscreen, Light explains that drawing upon her considerable skills as an actor to make those moments convincing wasn’t hard to do.

“It was not difficult at all, and it wasn’t like I had to reach in and sort 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 thinking about it.”

In portraying Lynn, whom the trailer hints at being unwell, Light was able to easily and comfortably explore her character’s complicated journey.

“What does it tell you that somebody is not well? What’s happening? What’s happening to the body? What’s breaking down? It was not difficult by any means, and Billy was so supportive and so incredible,” says Light.

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

“There’s nothing he can’t do. … He did Mr. Saturday Night [A New Musical Comedy] where he’s singing and doing eight shows a week,” she says of his 2022 Broadway performance. “And I know he’s done dramatic work before. … I don’t hold Billy as, ‘Oh, yeah, that’s the comedy guy.’ He’s this incredibly versatile artist that’s my friend. I knew somewhere the substance that he would bring to this.”

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Before premieres Friday, Oct. 25 on Apple TV+.