Cracking the Equation: Thomas Kail Is Making a PROOF for a New Generation

Being back on Broadway is never something Thomas Kail takes for granted.

As he prepares to bring Proof back to the stage, the Tony-winning director is approaching the beloved play with both reverence and curiosity. Kail is focused on rediscovering what makes the piece resonate, 25 years after its debut. It’s about honoring what came before while opening the door to something new.

“Being on Broadway is so special,” Kail reflected. “Getting into a rehearsal room to do a play anywhere is a miracle. The fact that we get to rehearse this play and then go to the Booth Theatre… you don’t think those things actually happen until you're walking to the theatre or going in the stage door. I'm so proud to be a part of this production—a chance to bring this terrific play to a new audience, to people that loved it when they first saw it, and to let them come to the Booth and see what we're doing.

“Our hope is to do something that's a companion to what exists before,” he explained. “We're not making the same play—we're trying to honor this play. And so having David Auburn in the room has been huge. We're just delighted to have a chance to try to crack it together.”

For Kail, that sense of openness has been hard-won. He admits that early in his career, he felt pressure to have all the answers—an expectation he’s since learned to let go of. “When I was a younger director, I always looked like I was 10,” he said with a laugh, “and I probably had something in my head that the director had to have all the answers. I was quite capable of saying to an actor or designer, ‘I don’t know, let’s figure it out,’ but I wasn't giving myself the same opportunity.”

That shift began around the time of In the Heights and has continued to shape his process ever since. “Once I relinquished that notion, I realized I don’t have to solve everything. It’s about identifying the finest idea, and knowing that the best idea on Tuesday might not be what we do next Thursday—and that’s okay too.”

That philosophy carries directly into the rehearsal room, where Kail sees his role less as a singular visionary and more as a collaborator. “If you're in a room with people who are playing above the rim and working at a high level, and you're not listening and helping sift and sort and suggest and edit and elicit—then you're not doing your job,” he said. “I love being in a room where there's no pressure for anyone to solve for. We also have material that you don't have to solve for—we're not trying to polish it up to get it by. We're trying to honor, and that’s a very particular thing you can only do when you have the right words.”

Those 'right words' are part of what has made Proof endure for a generation of artists and audiences alike. “I’ve mostly worked on new material that then, for some reason, hits a nerve,” Kail said. “And now we meet people auditioning for Hamilton who grew up with it. Show me an actor who hasn’t done a scene from Proof! I’m not sure where they are.”

It’s a testament, he believes, to the play’s emotional honesty. “This play was unafraid to put real human emotion front and center—to let you laugh and try to move you in the same scene. It talks about fathers and daughters, the struggle between siblings, and what it means to grapple with what we inherit—the things we’re given that we might not ask for. It was written 25 years ago, but I know it’s going to ping. It’s going to resonate. All of those things have so much truth in them—it just rings out.”

And in a time when audiences have more entertainment options than ever, Kail sees Proof as a reminder of why theatre still matters. “If we tell audiences now, ‘theatre is for you’—whether you're 50 years old or 15 years old—that’s what makes the next generation of theatregoers,” he said. “You have to make a lot of decisions to walk into a Broadway theatre. There are a lot of things that can keep you on the couch. But what this play reminds us of is the feeling of being with community—sitting shoulder to shoulder in the dark and watching a story be told. There’s nothing like it.”

Proof will open at the Booth Theatre on April 16, 2026.

Photo Credit: Andy Henderson