After attempts to match the course of an asteroid for cover result in collision with the asteroid and severe damage to Scorpio's engines, the crew search for an experimental stardrive developed by an ex-Federation designer who is now working for a terrorist group.
| Name | Type | Role | |
|---|---|---|---|
| Jim Follett | Writer | ||
| Damien Thomas | Guest Star | ||
| Peter Sands | Guest Star | ||
| Leonard Kavanagh | Guest Star | ||
| Barbara Shelley | Guest Star | ||
| David Sullivan Proudfoot | Director |