Sigmund Rosenblum is on a mission in Russia. His train is stopped and he is arrested, but he escapes and travels to London. There, he compromises Margaret Thomas, the young wife of a rich clergyman. Her husband dies, Rosenblum marries her, takes her maiden name (becoming Sidney Reilly) and is posted to the Far East.
| Name | Type | Role | |
|---|---|---|---|
| Troy Kennedy Martin | Writer | ||
| Leo McKern | Guest Star | ||
| Jim Goddard | Director |