On the lifeless star city Haven, the Doctor and Lucie encounter robot civilisations waiting for humans — and something far more dangerous lurking below.
| Name | Type | Role | |
|---|---|---|---|
| Teddy Kempner | Guest Star | Macrinus / Crusher | |
| Oliver Senton | Guest Star | Probus / Ripper | |
| Beth Chalmers | Guest Star | Elevator Voice | |
| Nigel Lambert | Guest Star | Domitian / Diode | |
| Phil Davis | Guest Star | Titus |