The Doctor arrives to join the battle, but is he too late to save both Sarah Jane and the Earth itself?
| Name | Type | Role | |
|---|---|---|---|
| Gareth Roberts | Writer | ||
| Paul Marc Davis | Guest Star | Trickster | |
| David Tennant | Guest Star | The Doctor | |
| Zienia Merton | Guest Star | Registrar | |
| Nigel Havers | Guest Star | Peter Dalton | |
| Mina Anwar | Guest Star | Gita Chandra | |
| Ace Bhatti | Guest Star | Haresh Chandra | |
| Joss Agnew | Director |