Reluctant to return to Moscow at the conclusion of his tour of duty as rezident in Canberra, Australia, Petrov negotiated his defection with the Australian Security Intelligence Organisation (ASIO) in April 1954. He had not disclosed his plans to his formidable wife Evdokia, a Soviet intelligence officer herself, and she made a dramatic escape from her plane in Darwin while being escorted back to the Soviet Union. Previously they had both served for three years at the rezidentura in wartime Stockholm and were experienced officers.
Petrov’s disclosures in Australia led to the appointment of a royal commission to investigate allegations of espionage, and ASIO took the opportunity to introduce suspects who had been implicated not by Petrov, but by VENONA material. The Petrovs were resettled in the Melbourne suburb of Bentleigh under the alias Sven and Anna Allyson; he died there in 1991, and she survived him until 2002. Reportedly the KGB learned of their new identities and whereabouts, but decided against their assassination.