Waking up on an alien planet with no name and no memory, a man discovers that the only ally ready to bring him home is not flesh and blood at all. He has only a few hours to trust the voice inside his own consciousness and make a choice, the price of which is disproportionately higher than one life. This is how a four—light-year journey begins - and into an infinity of questions about what it means to be the last or the first...