The Doctor and Sarah head to the meditation centre to try and get the crystal back while Lupton prepares to return it to Metebelis Three. But all their plans are disrupted when it is stolen by Tommy.
| Name | Type | Role | |
|---|---|---|---|
| Barry Letts, Robert Sloman | Writer | ||
| Ralph Arliss | Guest Star | ||
| Gareth Hunt | Guest Star | ||
| Kismet Delgado | Guest Star | ||
| Geoffrey Morris | Guest Star | ||
| Jenny Laird | Guest Star | ||
| Joanna Munro | Guest Star | ||
| Maureen Morris | Guest Star | ||
| Barry Letts | Director |