Arriving on Space Station Nerva in its distant past, the Doctor, Sarah and Harry find its crew threatened by a mysterious plague. Discovering that things are not as they seem, they uncover a Cyberman plot to destroy Voga, planet of gold.
| Directing | Michael E. Briant | Director |
| Writing | Gerry Davis | Writer |
| Writing | Robert Holmes | Writer |
| Writing | Robert Holmes | Script Editor |
| Production | Philip Hinchcliffe | Producer |
| Sound | Carey Blyton | Original Music Composer |
| Sound | Peter Howell | Original Music Composer |
| Costume & Make-Up | Prue Handley | Costume Design |
| Art | Roger Murray-Leach | Production Design |
| Camera | Elmer Cossey | Camera Operator |
| Editing | Sheila S. Tomlinson | Editor |
| Sound | John Gatland | Sound |
| Costume & Make-Up | Cecile Hay-Arthur | Makeup Artist |
| Production | John Bradburn | Production Assistant |
| Crew | Dick Mills | Special Sound Effects |
| Lighting | Derek Slee | Lighting Director |
| Sound | Norman Bennett | Sound |
| Visual Effects | James Ward | Visual Effects |
