Alanis Morissette, Frances McDormand and Mike Myers have all made surprise appearances in this Luminato play

This week marks the start of Toronto’s 19th Luminato Festival, a three-week citywide celebration of the performing arts. Among the more than 1,000 artists in this year’s program is British playwright and performer Tim Crouch, whose experimental two-hander, An Oak Tree, now in its 20th year of production, is getting its Toronto debut at the Jane Mallett Theatre with ten performances from June 14 to 22.

But this is no ordinary piece of theatre. Each night, a different celebrity actor will take the stage having never seen the script before. The guest actor won’t be revealed until one hour before the show, but in the past, stars like Frances McDormand, Alanis Morissette, Mike Myers and Phoebe Waller-Bridge have made surprise appearances, and Toronto can expect a fresh dose of star power each night.

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The play follows a father grieving the loss of his daughter, who was killed in a car accident. After discovering that the driver responsible for his daughter’s death is a local hypnotist, the father tracks him down and confronts the hypnotist during a public show. The guest actor plays the role of the bereaved father while Crouch plays the hypnotist and doubles as the onstage director, guiding the guest actor through the script.

“At each performance, An Oak Tree regenerates,” says Crouch. “It’s like a lizard losing its tail and growing a new one. Each time, there’s an actor who doesn’t know the play. Each time, there’s the same invitation to the actor to trust their instincts and to leap into the unknown.” 

But even the most experienced actors can be made raw by grief—and that’s exactly what Crouch is after. “In the history of the show, I’ve had the privilege of working with some A-List stars, but An Oak Tree is a leveller,” he says. “Within minutes, the story removes any celebrity gloss, and we’re two human beings working it out as we go along.” 

While the full list of potential guest stars is still under wraps, the initial lineup already includes some award-winning heavy-hitters like Karen Robinson of Schitt’s Creek, Amrit Kaur of HBO’s The Sex Lives of College Girls and Jean Yoon of Kim’s Convenience. Also in the mix are some of Toronto’s finest thespians, including Qasim Khan of Canadian Stage’s The Inheritance and Governor General’s Award–winner Daniel MacIvor. With the door wide open for last-minute cameos, every night carries the thrilling possibility of seeing a big-time star.