The Quantum Mechanic. Time Layers - Brian Spychalla

The Quantum Mechanic: Time Layers is the second book in the Quantum Mechanic series, following Brian Matthews - a resourceful eighth-grader from Texas - and his tight-knit crew of friends as they navigate the dangers of multiverse travel.

With his uncle Harold locked away in a military prison and DINA - Harold's dimension-hopping 1956 Chevy Bel Air - stranded in another reality, Brian is on his own. When he uncovers Harold's secret theory explaining how every choice creates isolated, coexisting timelines called "layers," he begins to grasp the true scope of what his uncle built - and the target it's painted on their world.

Time Layers blends coming-of-age friendship, imaginative science fiction, and multiverse adventure, exploring themes of responsibility, trust, and the consequences of choices - both quantum and deeply personal.