As they cope with teenage bullies, a terrifying witch, and a weird mystery, two boys learn to be the heroes of their own adventure . . .

On a hillside above a Pennsylvania steel town in 1975, best friends Matt and Jerry are spending the summer between sixth grade and junior high school hauling wood to build the world’s most awesome treehouse. Everything goes as planned—until they have a run-in with menacing teens Jimmy Gemm and the Trio Diablo gang.

From there, a simple summer only gets more complicated—especially when they venture into the secluded hollow on the other side of the hill, where they stumble upon a sinister witch and her raving captive. But everything is not as it seems, and the boys will have to face their fears if they want to solve this strange mystery and finally get to hang out in their treehouse . . .