Settling into officer's quarters after Lister concludes his inverse pregnancy, the crew welcomes back a new member and Holly decides to have a head sex change. With no time to get acquainted with their new company and surroundings, the crew are sent into a universe where time runs backwards, are left to starve on an ice moon, face an emotion sucking monster, swap bodies with each other, travel back through photographs, and face the threat of their new crew-member's state-of-the-art replacement.