In Biggles Buries a Hatchet, Lieutenant Vostov was a Cossack officer who was stationed at the prison of Onor on the Russian island of Sakhalin. Ex-prisoner Ivan Miskoff described Vostov as a hateful man who was himself a thief before he was sent to Sakhalin as a prison guard. Vostov would often ride out with his Cossack escort to terrorize the ex-prisoners who lived in the huts along the river near the prison. Miskoff blamed Vostov for the suffering he had undergone and for the death of his wife and vowed to kill him.
Towards the end of the book, in the commotion that followed the discovery that von Stalhein was missing from the group of convicts working at the coal face, Vostov rode out with his Cossacks in pursuit. As his troop was about to cross a bridge and close in on Biggles and von Stalhein, Bertie threw a few sticks of dynamite onto the bridge which blew it up and panicked Vostov's horses. After regaining control of his horse, Vostov next attempted to cross the river further up at a ford but was shot by Miskoff.