With the TARDIS occupants trapped in a chronic histeratic loop (forever reliving the same moment in time), the devious Meglos - disguised as the Doctor - gains the trust of the Tigellans along with full and private access to their power chamber.
| Name | Type | Role | |
|---|---|---|---|
| John Flanagan, Andrew McCulloch | Writer | ||
| Christopher Owen | Guest Star | ||
| Frederick Treves | Guest Star | ||
| Bill Fraser | Guest Star | ||
| Jacqueline Hill | Guest Star | ||
| Simon Shaw | Guest Star | ||
| Crawford Logan | Guest Star | ||
| Colette Gleeson | Guest Star | ||
| Edward Underdown | Guest Star | ||
| Terence Dudley | Director |