Two invincible foreign agents escape from the ultimate prison, a monastery run by the security services. They resume their mission, to kill one important person each. Steed and Tara set out to catch them, and to find out how they escaped, before their leader follows suit.
| Creator | Sydney Newman |
|---|---|
| Actor | Patrick Macnee, Linda Thorson, William Lucas |
| Country | United Kingdom |
| Production | Associated British Picture Corporation |