Whenever an artist or performer draws attention to the mechanics of their own work, it's worth asking why. Tom Stoppard extended Shakespeare's "all the world's a stage" in Rosencrantz and Guildenstern Are Dead to reinforce life's basic lack of narrative continuity. When Scott McCloud created a cartoon version of himself in Understanding Comics, it was illustrate how our mind extrapolates a face from two dots and a line. And if you're watching a Brecht play and someone holds up a cue card, you're probably supposed to start thinking about the plight of the proletariat.

This why is the central question of Tim Crouch's An Oak Tree, a show that does fast, efficient work on both intellect and emotion over its hour-long runtime.

The show is performed by two actors; Dennis Kelly, in the role of a two-bit stage hypnotist; and another actor who has never seen or read the play before, and who changes every performance. (On the afternoon I attended, this part was played by Catherine Olson.) At show's beginning, Kelly explains the premise of the show to the audience, and introduces the guest actor for that day's performance. The actor will be playing the role of a father, Kelly explains, whose daughter has been killed in a car accident. The daughter was killed by Kelly, as a matter of fact, and the father has to come to Kelly's show to talk about his daughter's death.

The actor playing the father is guided through the show by Kelly, using a combination of spoken stage direction, whispered lines of dialogue, and clipboards containing bits of the script. The show is entirely un-improvised, but it is as new to the actor playing the father as it is to the audience.

Through this fairly convoluted device—which works seamlessly and is fascinating to watch in action—a story emerges, of a father grieving so strangely and poorly for his lost daughter that he risks losing all he has left. It is undeniably compelling, funny, and heartfelt. It's also a bit of a puzzle.

Perhaps it's best left to individual audience members to determine the why of this setup—why interpose layers of manipulation and technology and uncertainty between performers and the truth of the story they're telling? Or maybe that very question hints at an answer.