The planet Helotrix is falling easily to attack from a new Federation pacification drug, as are many other star systems. Tarrant and Dayna teleport down to the surface to investigate. There they find a rebellion in full swing, with the enemy using a drug to prevent the population from attacking.
| Name | Type | Role | |
|---|---|---|---|
| Robert Holmes | Writer | ||
| Christopher Neame | Guest Star | ||
| David Quilter | Guest Star | ||
| Robert Morris | Guest Star | ||
| Cyril Appleton | Guest Star | ||
| Edgar Wreford | Guest Star | ||
| George Lee | Guest Star | ||
| Nick Brimble | Guest Star | ||
| Malcolm Stoddard | Guest Star | ||
| Neil Dickson | Guest Star | ||
| John Quentin | Guest Star | ||
| David Sullivan Proudfoot | Director |