The Purge traces a dark and little-known moment in Canadian history: the systemic discrimination faced by members of the LGBT community within the Armed Forces and the federal public service. From 1950 to 1996, it was yesterday, no effort was spared to flush out these men and women deemed "immoral" and representing a "danger to national security": intensive and coercive interrogations, humiliating tests, polygraphs, forced confessions and denunciations.