THE 38TH CENTURY: TRITON, ONE OF THE MOONS of Neptune, has been colonised by humans and is home to a thriving, capitalist civilisation. Its prosperity has been made possible largely by the development of a technology that can accelerate sleep, to the point where those who use it can function without sleeping for a month.
The Morpheus process (named after the Greek god of dreams) has been developed by Professor Gagan Rassmussen in his research station Le Verrier, positioned in orbit around Neptune. All communication from Le Verrier ceased 24 hours before the Doctor and Clara arrived at the apparently deserted artificial satellite. The time travellers meet a military rescue squad, dispatched from Triton to find out what happened and search for survivors.