The Spare-Part People (unproduced TV story)

The Spare-Part People, also known as The Brain Drain and The Labyrinth was an unproduced script written by Jon Pertwee and Reed De Rouen for Season 8. It was submitted in the summer of 1970, but was rejected after the production team decided they wanted the Master to feature in every story that season. Pertwee tried to rework the script, but Rouen was attached to the original version and stepped down from the project altogether. Pertwee later stepped down as well.

The first version saw the Doctor investigating a series of disappearances at Cambridge University by posing as a don there. The second version saw the Doctor and UNIT coordinating with international military services to hunt down the Master. In both versions, this led the Doctor to Antarctica, where he found a stranded alien crew that was kidnapping humans and using their organs to sustain themselves. He would have defeated them by welding their ship's exits shut, so they would have to fix their engines and leave Earth to survive.

In the second version, Pertwee suggested that these aliens were the ones who called the Master to Earth, hoping that he could kill the Doctor and prevent any chance of them being discovered.