Leo, Harry and Nikki step up their efforts to discover the truth behind the train crash but there are still many unanswered questions.
| Name | Type | Role | |
|---|---|---|---|
| Michael Crompton | Writer | ||
| Jay Martin | Guest Star | Private Vickery | |
| Patricia Kerrigan | Guest Star | Katie Wiltshire | |
| Paul Hilton | Guest Star | William Gould | |
| Robyn Cooper | Guest Star | Alice Christie | |
| Sean Murray | Guest Star | Joe Moss | |
| Eddie Marsan | Guest Star | Derek Poutney | |
| Nicholas Hewetson | Guest Star | Peter | |
| Michael Webber | Guest Star | Maurice Garton | |
| Emma Cunniffe | Guest Star | Rosa Christie | |
| Kate Bickford | Guest Star | Woman | |
| Kieran Bew | Guest Star | Stephen Wiltshire | |
| Shaun Parkes | Guest Star | DI Freeman | |
| Colin Tierney | Guest Star | Thomas Christie | |
| Clare Wilkie | Guest Star | Emilie | |
| Simran Sandhu | Guest Star | Sarah Baker | |
| Dave Hill | Guest Star | Mr Hall | |
| Danny Webb | Guest Star | Sergeant Paul Bradley | |
| Stephen Boxer | Guest Star | Major Mark Wiltshire | |
| Talisa Garcia | Guest Star | Suzi Bradley | |
| Jane Wood | Guest Star | Mrs Hall | |
| Amita Dhiri | Guest Star | Diana Baker | |
| Douglas Mackinnon | Director |