Joaquin Phoenix says that his role in 'C'mon C'mon' restored his love for acting: 'Every day was alive and different'

Hollywood legend has it that ornery comedy superstar W.C. Fields had one guiding principal for all of his movies: "Never work with animals or children." Due respect to Fields, but Joaquin Phoenix — who shares the screen with 11-year-old Woody Norman in the acclaimed new drama, C'mon C'mon — would disagree. "Our old pal W.C. never worked with Woody," Phoenix tells Yahoo Entertainment with a laugh. "He was the spotlight of our lives [during production] and becomes the focus of the movie, and we f****** encouraged that."

Written and directed by Mike Mills, C'mon C'mon is Phoenix's first star turn since the actor's Oscar-winning performance in Todd Phillips's divisive DC Comics adaptation, Joker. And in terms of appearance and personality, his hangdog public radio journalist, Johnny, isn't even in the same zip code as the rail-thin, emotionally disturbed Arthur Fleck. Johnny's main beat is talking to kids about their hopes, dreams and fears for the future, but he leads a childless single guy existence when the mics are off.

That changes when his sister, Viv (Gaby Hoffman), needs to care for her bipolar husband (Scooter McNairy), and asks Johnny to watch after his nephew, Jesse (Norman) — a precocious kid he hasn't clocked many in-person hours with. Unable to take the time away from work, he ends up bringing Jesse on the road with him and gets a crash course in what it means to care for a child.

Mills was inspired to write C'mon C'mon based on his own experience as a father. (He shares a young son with his wife, filmmaker Miranda July.) "The only reason I could do this film is because of all the gifts my kid gave me," the writer/director says. "I wanted to write about all the time I spent as a dad, and that stage of being with a young person — trying to give them full respect and not treat them as cute or sweet or anything like that. You want to treat them as a full being and all the challenges, vulnerabilities and love that they give back to you."

Phoenix welcomed his own son — reportedly named after his late brother, River Phoenix — with his partner, Rooney Mara, just before production on the film began. The actor declines to discuss that side of his life, but he is willing to reflect on his own experience as a child star in the 1980s and how it informed both his on and off-screen relationship with Norman.

Phoenix's earliest roles were guest spots on such era-defining TV shows Hill Street Blues and The Fall Guy, before graduating to high-concept feature films like SpaceCamp, Russkies and Parenthood. (He was credited as "Leaf Phoenix" during that period of his career, reverting to his birth name with Gus Van Sant's 1995 dark comedy, To Die For.)

"I remember talking to Mike, and just saying how fortunate Woody was to have this as one of his early experiences making movies," Phoenix says now. "I remember witnessing this one moment of Woody seeing a new side of Jesse in a particular scene. That was something that was familiar to me: I remember having similar moments when I was around that age, and it was incredible for me to witness someone else having that experience, because it's something I've been chasing ever since then."

"The truth is that when you make so many movies, inevitably there are times where inspiration can wane," Phoenix continues. "Working with Woody, I was constantly reminded of what I love about acting. Every day was alive and different; you didn't know what to expect in the best way."

While Mills knows of Phoenix's own child star past, he admits that SpaceCamp and Russkies passed him by when he was going to the multiplex in the '80s as a teenager. "My moviemaking has always been so pretentious, so I haven't seen a lot of those movies," he says, laughing. "What I liked about making C'mon C'mon is inserting a kid into a naturalistic, adult-y film. That's exciting to me, and I felt really confident that I was going to an interesting place."

As Mills recalls, finding a kid who could deliver the kind of naturalistic performance he was after was the production's biggest challenge. "Joaquin was always the person I wanted for the role of Johnny, and we were both like: 'Who the hell is going to play Jesse?'" If we couldn't find someone we really believed in, then we didn't have a film." That led to several casting sessions where Phoenix would "hang out" with different kids, acting out portions of the script or just playing around for the camera.

"Woody just leapt out [of that group]," Mills says. "He was a kid with comic timing, and they felt like two strong souls and two smart people to me. One of the important themes of the movie is that they're similar, and not just because of the genetic stuff. Their souls have a similarity, and I bought that when I saw the image of Joaquin and Woody together."

C'mon C'mon premieres Friday, Nov. 19 in theaters.