Life After Life is an engaging puzzle that spans two world wars. With the introduction of Ursula Todd, a woman who relives her life over and over, Kate Atkinson poses endless, fascinating questions: What would the world be like if we could start over when things went terribly awry? Could our decisions, big and small, avert wars? Make us happier? Stop death in its tracks? Life After Life is rich with history and possibility, and it left my brain humming.