Hedge is a typical human--fat and bald, not pretty but not ugly, with a round, doting wife, and a farm where he tends beehives. Except Hedge is not a typical human. In fact, Hedge is not human at all, but a plant sent by the Council of Plants and the Plant of Ultimate Knowing to observe humanity and determine whether or not humanity is a threat to the universe. A task he has blithely performed for twenty years. Until the night he receives a message to report back to the Council and realizes he has to leave everything behind.

Pursued by an agent of the notorious Visitors, whose appearances have heralded the end of civilizations, torn between his fellow plants and an awakening affection for his earthwife, Anna, and armed only with a toaster, Hedge must find a way to save humanity from Visitors, plants, and themselves.