By Leah Greenblatt
October 18, 2019 at 03:55 PM EDT

Like last year’s festival breakout Three Identical Strangers, Ed Perkins’ Tell Me Who I Am is another documentary about siblings with a terrible secret at its center.

Unlike Strangers though, the deception here is ultimately an act of love: British-born brothers Marcus and Alex Lewis, now in their early 50s, are identical aside from the rough graze of salt-and-pepper stubble on Marcus’ face — and the fact that nearly everything Alex knows about his life before the age of 18 comes directly from his twin.

After a motorcycle accident, Alex wakes up from a coma with no memory of who he is or where he came from: He doesn’t recognize his home, his family, or his own name, but he knows he knows his brother. So he relies on Marcus to teach him all the things he’s lost, from Tom and Jerry to how to make toast, and even gently reacquaint him with his own girlfriend.

What Marcus doesn’t tell him is why they live together in a shed on their parents’ property, don’t eat meals with them or have proper house keys. Alex recognizes that his father seems distant — when he returns from the hospital, he’s just a man who re-introduces himself, with a firm handshake — and his mother eccentric. Still, he seems happy enough to take everything he’s told on faith, and soon learns little tricks to help ease himself back into some semblance of a normal life.

But as Marcus asks at one point, “What is normal, really? Normal is what you know. Normal is what your family is.” And what Alex has been told to believe about all of that is profoundly disconnected from what he finds one day in their parent’s attic — which is where the brothers’ relationship begins to unravel, and the movie finally breaks the tension it’s been building toward inexorably.

Perkins (Black Sheep, If I Die On Mars) has both siblings’ full cooperation, including a trove of family photos and videos and most crucially, their commitment to radical honesty in nearly every scene. His tendency to rely on somewhat hammy TV-style dramatic recreations feels unnecessary with the raw material they both provide, and there’s a sense too of drawing out certain moments for effect that need no embellishment.

But the truth, when it does come out, is devastating — to the point that it can feel invasive to watch such a profoundly private moment unfold on camera for our benefit. That Perkins has honed in on such sympathetic subjects makes it almost impossible not to be moved, even if Tell Me often feels less like forensic truth than an intriguing fragment of a story that may, in the end, be impossible to tell in full. B

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