A Traveller wakes on a remote planet with amnesia and must repair their crashed starship. Compelled by an unknown force to reach the centre of the galaxy, the Traveller encounters three alien species and discovers a space anomaly housing two beings, Nada and Polo, who speak of a strange entity at the galaxy's core. Along the way, the Traveller receives transmissions from another lost Traveller named Artemis, investigates their fate, and ultimately comes face to face with the Atlas, a cosmic being managing a simulated universe. The Traveller must choose whether to reset the simulation or reject the Atlas and continue exploring freely.