- The 'Cambridge Five' were a group of upper-class British spies recruited by the Soviets at Cambridge University in the 1930s, who later held high positions and leaked secrets to Moscow.
- Their betrayals led to failed missions and deaths, such as the 1951 Ukraine parachute drop of anti-communist Ukrainians, which was compromised by Kim Philby's tip-off.
- Antonia Senior's book 'Stalin's Apostles' focuses on the human cost of their actions, stripping away romanticism and highlighting their negative impact on lives and U.S.-British relations.
- The spies were shielded by their elite backgrounds and the 'chapocracy' of mid-century Britain, which made it hard for authorities to suspect them despite red flags like alcohol issues and communist ties.
- After the ring collapsed, consequences were mild for some; Kim Philby, for example, faced limited evidence and worked as a journalist in Beirut before defecting to the USSR in 1963.