Petrov decided to join the Soviet spy organization, then called the
OGPU, in May 1933, while serving in the Navy. He was subsequently admitted to the
Special Cipher Section, which was attached to the
Foreign Department of the OGPU. His memoir makes clear that his status in this section allowed him to learn many Soviet secrets by reading the top secret ciphers. Petrov's joint memoir with his wife Evdokia Petrov's joint memoir, Empire of Fear, gives the following details about his career between 1930 and 1954. The book,
Empire of Fear, was ghost-written by an ASIO intelligence officer, Michael Thwaites, serialised in newspapers in 1955, and published in book-form in 1956. • 1930–1933
cypher clerk Soviet Navy. • 1933–1937
NKVD Moscow dealing with overseas cypher communications. • 1937 NKVD cypher clerk attached to
Soviet Army Western China. • 1940–1942 NKVD cypher clerk Moscow dealing with Internal communications. • 1942–1947 NKVD cypher clerk Sweden with additional Internal Security duties. • 1947–1951
MGB Moscow handling cases of Soviet seamen accused of offences while visiting foreign ports. • 1951–1954 MGB controller in Australia. Having graduated from cipher clerk to full-fledged agent, Petrov was sent to
Australia in 1951. His job there was to recruit spies and to keep watch on Soviet citizens, making sure that none of the Soviets abroad defected. Petrov lived through the purges of
Stalin under
Yagoda,
Yezhov, and
Beria. Even though a great number of his friends, colleagues, and superiors were arrested and executed, Petrov escaped unscathed. == Defection ==