February 11, 1910 is the date Kate Atkinson's novel returns to again and again: the night Ursula Todd is born in a snowstorm in an Oxfordshire farmhouse. In one iteration she is stillborn; in others she drowns as a child, dies in the Blitz, or survives long enough to kill Hitler — each life beginning again from this same winter night, the novel asking how the smallest variations in circumstance can reshape an entire century.