"What happens when we die? Does the light just go out and that's that - the million-year nap? Or will some part of my personality, my me-ness persist? What will that feel like? What will I do all day? Is there a place to plug in my laptop?"

In an attempt to find out, Mary Roach brings her tireless curiosity to bear on an array of contemporary and historical soul-searchers: scientists, schemers, engineers, mediums, all trying to prove (or disprove) that life goes on after we die. She begins the journey in rural India with a reincarnation researcher and ends up in a University of Virginia operating room where cardiologists have installed equipment near the ceiling to study out-of-body near-death experiences. Along the way, she enrolls in an English medium school, gets electromagnetically haunted at a university in Ontario, and visits a Duke University professor with a plan to weigh the consciousness of a leech. Her historical wanderings unearth soul-seeking philosophers who rummaged through cadavers and calves' heads, a North Carolina lawsuit that established legal precedence for ghosts, and the last surviving sample of "ectoplasm" in a Cambridge University archive.