The post-war re-Sovietisation of the West-Ukrainian territories encountered strong resistance on part of the Ukrainian nationalist insurgents (OUN and UPA), who were massively supported by the West-Ukrainian population. To fight these Ukrainian “banditry” groups, the Soviet authorities employed numerous military units that were dislocated into western Ukraine shortly after the war. The struggle between the Ukrainian insurgents and the army rarely resulted in massive military confrontation but guerrilla and underground operations were the norm. The Soviet security forces tried to infiltrate Ukrainian insurgent units by employing informants and creating networks of secret agents. Petrenko demonstrates that such Soviet tactics proved surprisingly successful and many Ukrainian insurgents, in particularly women, became employed as Soviet agent. The author analyses how and why so many Ukrainian insurgent women agreed to involve in Soviet secret services, and examines in details Soviet mechanisms of recruiting new agents.