It's 1891, and Willa Marconi's mentor has just died—but she'll never stop researching. While testing her prototype radio equipment, she detects a mysterious signal. In 2034, a cataclysmic event has rendered the Earth uninhabitable, and humankind survives by living inside of artificial worlds. Riley would do anything for Jaideep, who lost his parents in the collapse of the Bay Area pocket universe—and anything includes building a time machine so they can travel back in time and rewrite history. But the experiment goes wrong and strands all three of them in a time that's not their own. Now they’ve got a glitchy time machine, a scary android time cop hot on their trail, and tangled temporal mechanics to unravel. Can they save the Earth when the Continuity Agency is dead-set on preserving the current timeline?