The Rani has returned with another malicious scientific scheme. Taking advantage of the post-regenerative trauma the recently regenerated and unstable Doctor is going through, she hopes to achieve control of an approaching asteroid composed entirely of strange matter. Can the Doctor figure out he is being used for the Rani's evil experiment, and what is behind the door the Rani won't allow him past?
| Writing | Jane Baker | Writer |
| Writing | Pip Baker | Writer |
| Costume & Make-Up | Ken Trew | Costume Design |
| Art | Geoff Powell | Production Design |
| Art | Oliver Elmes | Graphic Designer |
| Sound | Keff McCulloch | Original Music Composer |
| Costume & Make-Up | Lesley Rawstorne | Makeup Artist |
| Camera | Alastair Mitchell | Camera Operator |
| Camera | John Hawes | Camera Operator |
| Lighting | Ian Dow | Lighting Director |
| Sound | Doug Whittaker | Sound |
| Production | John Nathan-Turner | Producer |
| Production | Joy Sinclair | Production Assistant |
| Production | Tony Redston | Production Manager |
| Writing | Andrew Cartmel | Script Editor |
| Lighting | Henry Barber | Lighting Director |
| Visual Effects | Dave Chapman | Visual Effects |
| Editing | Hugh Parson | Editor |
| Visual Effects | Colin Mapson | Visual Effects Designer |
| Sound | Brian Clark | Sound |
| Directing | Andrew Morgan | Director |
