After a successful launch, the talented crew of the MTS42 begin their two year mission to bring life to Mars. But their smooth start comes to a halt when Marina Barnett (Toni Collette), the ship's commander, finds launch support engineer, Michael Adams (Shamier Anderson), on board by accident. With not enough fuel to turn back and bring Michael home, the crew must help him prepare for what's to come in order for all of them to survive.