For thousands of years, it has drifted through space, unimpeded, forgotten, seemingly lifeless. Now, finally, it has been discovered.
Responding to a distress call from the mysterious hulk, the Doctor and his companion, space pilot Mathew Sharpe, walk into a desperate situation. The multi-tentacled semibionic Makara were tasked with renovating the abandoned craft, but now they've begun murdering their employers.
The Doctor soon realises that the Makara have been programmed to kill, but by whom, and for what reason? Finding out the truth will mean uncovering a secret that threatens the entire Universe.