During a Christmas open-mic night in New York, a new face took the stage under the name Alex Novak. He was moderately funny, clearly dealing with personal issues, and his set centered on the emotional fallout of a divorce. What stood out the most, though, was how much he resembled Will Arnett, known for roles in Arrested Development and other popular works.

“I had no idea what I was getting into,” recalls Arnett, nearly a year later. “I’ve worked around comedians for years, but never actually been one.”

So began an intense dive into the world of personal comedy. Arnett performed five nights a week for six weeks across New York. Each performance was prepared that day and delivered to unaware audiences. He tried to block out anyone who recognized him from his various roles in film and television.

This was all part of the groundwork for his first lead role in a serious film, where he plays a man who’s offered free entry into a bar’s comedy night if he performs for five minutes. That decision sets him on a path of discovery.

“Taking the stage always feels like jumping into the void,” Arnett explains. “It’s terrifying.” Some nights were a hit. “One place, I was getting big laughs. Then I went to another club nearby and completely died with the same routine.”

Arnett, tall and broad, doesn’t mask how painful failure felt. “When it goes bad, you feel exposed. You walk off just stunned. The only laugh that night came from the back—and it was Bradley.”

That would be Bradley Cooper, in his third venture as a writer-director. He plays Arnett’s on-screen best friend, an egotistical actor named Balls. Also in the audience that night was Andra Day, playing Balls’ sharp-tongued wife, Christine.

“It was wild watching Will react to no laughter,” Day says, amused. “You could see it in every little move, like his head was physically rejecting the silence.” As a performer herself, Day understands that sinking feeling when a performance doesn’t land. “But at least I can say, ‘Let’s move on to the next song!’”

Arnett found it tough to rebound from a poor reception. “You try to dial up your energy,” he says, “but that only makes things worse. Comedy is more interactive than I understood. They need to feel part of it, to buy into the story. You have to wait, let them settle into it.”

Cooper’s films often delve into this dynamic between performer and audience—how seeking validation can either uplift or drain. Whether in A Star Is Born, Maestro, or now Is This Thing On?, these moments often occur during live performances. “Each time, the emotional connection happens when authenticity is exposed,” Cooper explains in a carefully crafted email response.

In this film, that moment comes when the ex-wife of Arnett’s character, Tess (played by Laura Dern), stumbles upon his comedy act during a date. Surprised by his sincerity and vulnerability, she begins to see the man she once loved in a new light. “She sees him clearly again,” Cooper reflects.

Speaking from her London hotel, Dern leans in with passion. “It’s so touching—the idea of committing to unhappiness in a relationship,” she says. “We’ve all been there, wondering how we got so lost. This film really changed my perspective on what commitment means—it’s not a steady destination but a continual journey. We evolve.”

In the movie, Alex and Tess reconnect as they each pursue newfound passions—his being stand-up, hers, basketball. The message emphasizes that real change and mutual understanding come from personal growth. It’s not always about bliss; sometimes, enduring unhappiness together is the deepest kind of connection.

Dern, now 58, wonders if her generation is too stuck to change. Her own kids, Ellery and Jaya, seem wiser. “They’ve grown up with a world of social media performance,” she says. “Now they’re craving something real. Just being messy, honest, and together.”

She cringes at the constant need for image management. “It’s like middle school all over—what skirt did I wear, what did I say to the boy? It’s exhausting!”

Next door, Day, 40, expresses a similar disdain for pretense. “Arrogance usually hides deep insecurity,” she notes. “We're all showing half of ourselves while protecting the rest. Once you let go of the act, you never want to put the mask back on.”

The film’s origin comes from Arnett’s chance meeting with British comedian John Bishop. Bishop first took the stage just to avoid paying a cover charge. That set him down a life-changing path, leading him back to the love of his life. In the movie, the jokes might falter, but sincerity carries the story. “If Alex keeps at this,” Arnett says, “he’s really going to need better material.”

Despite wider concerns about the future of American television comedy—Colbert’s show had just been canceled—Arnett remains thoughtful. “It’s always been tough. Comedians have always had to toe the line. That just means we have to be smarter now.”

For Arnett, the heart of the story wasn’t the comedy but the chance to delve into deeper emotional territory. “It required me to revisit my own life.” He quietly nods to his public separation from Amy Poehler, with whom he shares two sons. Though the script isn’t autobiographical, the emotional parallels are certainly there.

Unlike Cooper’s previous works, this film doesn’t center on megastars. Still, it deals with the cost of fame. In one moment, Alex blows up an old photo of Tess shooting a basketball. She’s not thrilled. “She doesn’t see herself in that image,” says Dern. “It’s just someone’s idea of her, frozen in time. We all face that—others clinging to who they think we were.”

Arnett admits it might come off as a privileged problem. “But seeing a version of yourself out in the world is strange. It never feels quite like you.”

Cooper avoids addressing that idea directly—but his choice to promote this film more quietly suggests a certain intentional distance. Compared to his enthusiastic campaigns for earlier films, this seems more subdued. Is This Thing On? is gentle but sharply observant, especially about how much of ourselves we should reveal in pursuit of honesty in art.

At one point in the film, Alex’s kids read a draft of his material and are unsettled. "That's not real," Alex reassures them. But it's clear that it is. So when does sharing personal truth cross a line into betrayal?

“I don't presume to define that for others,” Cooper says. “But if someone feels betrayed, emotionally, that experience has weight. I try to be cautious. Other people’s lives are part of those stories, even if they didn’t agree to share them.”

Cooper’s daughter, Lea, even appeared as young Bernstein’s daughter in Maestro. His latest film begins and ends with school talent shows. “Bradley said he went to one while preparing for this,” says Dern. “And there were kids performing their hearts out while parents stared at their phones. He was like, ‘There’s a lion dancing in front of us!’”

She shakes her head. “We’ve become so distracted. But when you wake up to yourself, you wake up to the moments with your kids. Even the ones we think are mundane.”

Cooper adds, “Watching a school play is deeply subjective. When your child is on stage, your whole emotional history comes with you. Everyone in that room is holding their own private reflections. That makes the experience quietly powerful.”

Some of the most moving scenes in the film feature school performances. “Children are transparent when they perform,” says Cooper. “They don’t worry about success. Their real feelings shine through. Ironically, that's exactly what adult performers spend their whole careers trying to recreate.”

Imagine dedicating your life to performance only to be outdone, effortlessly, by your own child. Still, Is This Thing On? argues that the struggle is worthwhile – that truth in adult expression can lead to healing.

Even Cooper admits that sometimes the effort feels more stressful than profound. “But even difficult moments, in retrospect, lead to release or insight.”

Dern agrees wholeheartedly. “It’s always cathartic,” she says. “Even playing difficult roles forces me to dig deep—and that’s valuable. Each character holds a part of me, however dark.”

Dern herself is poised and composed, but her passion for the project is clear. It’s easy to imagine her crushing a comedy set, had she tried.

She champions the film with enthusiasm. “It’s like a map for living without regret,” she says. Her son echoed her sentiment: “It’s the perfect film for someone starting life. It makes me want to be fully myself to love.”

She smiles proudly. “My generation was raised on fairytales – say yes when Prince Charming appears. This movie offers a better story.”

She gestures toward a television playing muted news. “I’m not sure how I keep checking in on the world before bed—it’s awful. But we need to shut that out and turn toward what matters: connection.”

Don't underestimate Is This Thing On?, Dern urges. It’s not just another comedy or industry story. It carries a powerful message. “There’s something deeply human about saying, ‘even if I’m unhappy, I want to be unhappy with you.’ It’s about sticking with life, despite the mess. We’re all here together. And if we don’t lead with love, we’re lost.”

Is This Thing On? is set to release in the UK on January 13.