The alien space station J7, the mid-1980s Earth time. The Time Lords have sent the second Doctor and Jamie here to try to stop dangerous experiments into time travel. But the station comes under attack from the Sontarans and far away in space and time the sixth Doctor goes into psychic shock...
| Name | Type | Role | |
|---|---|---|---|
| Robert Holmes | Writer | ||
| Nicholas Fawcett | Guest Star | ||
| Aimée Delamain | Guest Star | ||
| Frazer Hines | Guest Star | ||
| James Saxon | Guest Star | ||
| John Stratton | Guest Star | ||
| Carmen Gómez | Guest Star | ||
| Jacqueline Pearce | Guest Star | ||
| Tim Raynham | Guest Star | ||
| Peter Moffatt | Director |