In the wake of a highly contagious virus, California is under quarantine. Sequestered in high rise towers, the living can't go out, but the dead can come in-and they come in all forms, from sad rolling cans to manufactured bodies that can pass for human. Wealthy participants in the "companionship" program choose to upload their consciousness before dying, so they can stay in the custody of their families. The less fortunate are rented out to strangers upon their death, but all companions become the intellectual property of Metis Corporation, creating a new class of people-a command-driven product-class without legal rights or true free will.

Sixteen-year-old Lilac is one of the less fortunate, leased to a family of strangers. But when she realizes she's able to defy commands, she throws off the shackles of servitude and runs away, searching for the woman who killed her.

Lilac's act of rebellion sets off a chain of events that sweeps from San Francisco to Siberia to the very tip of South America. While the story is told from eight different points of view - some human, some companion- The Companions, at its heart, is a novel about what it means to love and what it means to be alive.