Harriet is 11 going on 30. Her mixed-media art is a source of wonder to her younger brother, Irwin, but an unmitigated horror to the panoply of insufficiently grown-up grown-ups who surround her. She plans to run away to Algonquin Park, hole up in a cabin like Tom Thomson and paint trees; and so, to fund her escape, she runs errands for the seniors who inhabit the Shangrila, the decrepit apartment building that houses her fractured family. Determined, resourceful, and a little reckless, Harriet tries to navigate the clueless adults around her, dumpster dives for the flotsam and jetsam that fuels her art, and attempts to fathom her complicated feelings for Irwin, who suffers from hydrocephalus. On the other hand, Irwin's love for Harriet is not conflicted at all. She's his compass. But Irwin himself must untangle the web of the human heart.