‘Shrinking’ Cast Gushes Over Watching Michael J. Fox Work on Season 3 (Exclusive)

Even though Michael J. Fox only shares the screen with Harrison Ford, the cast of Shrinking can’t stop gushing over watching the actor work on season 3. 

Fox, 64, made his return to acting with a three-episode arc on the new episodes of the Apple TV comedy starring Ford, 83, Jason Segel and Jessica Williams as a group of therapists all navigating personal and professional issues. 

In the first episode, which premiered Wednesday, Jan. 28, the iconic actor plays Jerry, a patient with Parkinson’s disease who befriends Paul (Ford), who has the same neurodegenerative disease Fox was diagnosed with in 1991. The two characters first encounter each other in the waiting room at a doctor’s office, before Jerry makes poignant appearances throughout the season. 

For cast members Williams, 36, Christa Miller and Luke Tennie, watching Fox on set was a “surreal” experience. 

“Every time I heard about some of these castings, it made sense,” Tennie, 31, tells PEOPLE, referring to Fox, as well as Jeff Daniels and Candice Bergen, who also have guest-starring roles on the new episodes. 

Williams says that she even hung around after she was done filming so she could see Fox work opposite Ford. “I stayed after I wrapped just to watch Harrison and Michael J. freaking Fox, one of the greatest actors ever, and it was very surreal,” she shares. 

“It was a pinch-me moment,” Williams continues. “It was really special. That was one of those where you stayed, even if you’re tired, you just stay and you just watch it happen. And that’s what I did. It was amazing.”

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Miller, 61, who is married to showrunner Bill Lawrence, 57, also appreciated that her husband and Fox got to reunite after first working together on Spin City. “He has had this beautiful relationship with Michael for many years and I think Mike had so much fun doing this show,” she says. 

“Harrison loved working with him,” Miller continues, adding that “there’s no one that has better comedic timing than Michael. I’ve never seen anything like it. It’s incredible. I saw what his words were and then I watched him do his first scene with Harrison and the timing that he brings to it, it’s like a masterclass. He has such good timing.”

Echoing that sentiment, Lawrence says, “It was awesome. It was so fun for me to see not only people that remember him from all these iconic things, but even young people that work on the show going, ‘That guy has crazy comedic timing.’ And he still does.” 

As for getting Fox back on-screen after the actor retired, the showrunners says, “I take great pride in being a person that continually takes him out of retirement.” Prior to reuniting here, Fox “came back and did Scrubs,” Lawrence’s medical comedy starring Zach Braff. 

When it comes to the character, Lawrence says it was guided by Fox. “He said, ‘I don’t care what I do as long as I’m playing just a guy.’ He was like, ‘I don’t want to play Mike Fox with Parkinson’s. I just want to play some dude,’ ” he says of Jerry. 

As for getting to work with Fox again, the executive producer says, “It meant more to me than you know.” He adds, “If we’re lucky enough to ever do a fourth year — we haven’t even talked about it yet — I would kill to have him do it again.”

Teasing what’s to come, Williams adds, “Michael J. Fox is amazing this season. He’s funny.” 

New episodes of Shrinking season 3 debut Wednesdays until April 8 on Apple TV.