Alan Bates and the sub-postmasters begin their fightback with new allies in Westminster, but first they must convince an independent investigator of their honesty.
| Name | Type | Role | |
|---|---|---|---|
| Gwyneth Hughes | Writer | ||
| Susan Brown | Guest Star | Min Howard | |
| Nicola Alexis | Guest Star | Consultant Psychiatrist | |
| Amit Shah | Guest Star | Jasgun Singh | |
| Esh Alladi | Guest Star | Hockum Salhan | |
| Caroline Gruber | Guest Star | Susan Crichton | |
| Krupa Pattani | Guest Star | Saman Kaur | |
| Isobel Middleton | Guest Star | Kay Linnell | |
| Lia Williams | Guest Star | Paula Vennells | |
| Ifan Huw Dafydd | Guest Star | Noel Thomas | |
| Conor Mullen | Guest Star | David Hamilton | |
| James Strong | Director |