There is a monument to Sorge in Baku, Azerbaijan. Sorge also appears in Osamu Tezuka's "Adolf" manga. In his 1981 book, "Their Trade is Treachery", the author Chapman Pincher asserted that Sorge, a GRU agent himself, recruited the Englishman Roger Hollis in China in the early 1930s to provide information. Hollis later returned to England, joined MI5 just before World War II began and eventually became the director-general of MI5 from 1956 to 1965. As detailed by former MI5 staffer Peter Wright in his 1988 book "Spycatcher", Hollis was accused of being a Soviet agent, but despite several lengthy and seemingly-thorough investigations, no conclusive proof was ever obtained.