Sarah Jane and the gang discover the secret of Erasmus Darkening - but are they too late?
| Name | Type | Role | |
|---|---|---|---|
| Phil Ford | Writer | ||
| Amelia Clarkson | Guest Star | Elizabeth Marchwood | |
| Floella Benjamin | Guest Star | Professor Rivers | |
| Rhys Gear | Guest Star | Joseph Marchwood | |
| Donald Sumpter | Guest Star | Erasmus Darkening | |
| Tony Boncza | Guest Star | Mr Scriven | |
| Callum Blue | Guest Star | Lord Marchwood | |
| Adam Gillen | Guest Star | Toby Silverman | |
| Alice Troughton | Director |