During the nuclear-charged 1960s, the KGB was active in sleepy Australian suburbia. For two years, the country’s security service, ASIO, secretly filmed meetings between a senior KGB officer, Ivan Skripov, and his British-born agent. Unknown to Skripov, she was a double agent - code name "Sylvia". Sylvia’s final rendezvous with an unknown "KGB illegal" operative held the promise of exposing a network of Soviet spies that had infiltrated the British atomic and rocketry facilities in South Australia.