The TARDIS arrives on 21st Century Earth where all long-distance journeys are made instantaneously by T-Mat. But aliens have invaded the T-Mat relay station on the Moon, and they're about to cause havoc.
| Name | Type | Role | |
|---|---|---|---|
| Brian Hayles | Writer | ||
| Philip Ray | Guest Star | ||
| Ric Felgate | Guest Star | ||
| Alan Bennion | Guest Star | ||
| Harry Towb | Guest Star | ||
| Steve Peters | Guest Star | ||
| Louise Pajo | Guest Star | ||
| Christopher Coll | Guest Star | ||
| Terry Scully | Guest Star | ||
| John Witty | Guest Star | ||
| Martin Cort | Guest Star | ||
| Ronald Leigh-Hunt | Guest Star | ||
| Michael Ferguson | Director |