The Time Lords send the Doctor and Jo on a mission to deliver a sealed message pod to an unknown party aboard a Skybase orbiting the planet Solos in the 30th century. They are caught quickly in a power struggle between the cruel Marshal of Solos and the young Solonian Ky over the future of Solos - a future that hinges on the contents of the message.
Unfortunately the movie Doctor Who: The Mutants is not yet available on HBO Max.
| Production | Barry Letts | Producer |
| Directing | Christopher Barry | Director |
| Writing | Dave Martin | Writer |
| Writing | Bob Baker | Writer |
| Sound | Delia Derbyshire | Theme Song Performance |
| Sound | Tristram Cary | Original Music Composer |
| Lighting | Frank Cresswell | Lighting Director |
| Costume & Make-Up | James Acheson | Costume Design |
| Art | Jeremy Bear | Production Design |
| Crew | Terry Walsh | Fight Choreographer |
| Camera | Fred Hamilton | Camera Operator |
| Editing | Dave King | Editor |
| Sound | Dick Manton | Sound |
| Costume & Make-Up | Joan Barrett | Makeup Artist |
| Crew | Dick Mills | Special Sound Effects |
| Writing | Terrance Dicks | Script Editor |
| Sound | Tony Millier | Sound |
| Visual Effects | John Horton | Visual Effects |
| Production | Fiona Cumming | Production Assistant |
| Production | Chris D'Oyly-John | Production Assistant |
