With Metebelis crystals spreading across Earth and the Eight Legs preparing to take control, the Doctor races to stop the invasion while Lucie becomes host to the Great One.
| Name | Type | Role | |
|---|---|---|---|
| Richard Earl | Guest Star | Rob | |
| Anthony Spargo | Guest Star | David | |
| Beth Chalmers | Guest Star | Queen | |
| Barnaby Edwards | Guest Star | Newsreader | |
| Stephen Moore | Guest Star | Clark Goodman | |
| Sophie Winkleman | Guest Star | Kelly Westwood | |
| Sanjeev Bhaskar | Guest Star | Dr Avishka Sangakkara | |
| Katarina Olsson | Guest Star | The Headhunter | |
| Kerry Godliman | Guest Star | Karen |