In contemporary American culture, it’s hard to think of a figure more universally praised than Martin Luther King. People across the political spectrum frequently cite King to buttress whatever their own beliefs are (often in sharp contrast to what King actually stood for). King has both a monument in the nation’s capital and a federal holiday, two honors mostly reserved for US presidents.

Yet when King was alive he was deeply reviled and maligned — including by US government institutions. A new documentary, MLK/FBI, explores how the Federal Bureau of Investigation surveilled and actually sought to destroy the civil rights icon.

The documentary recounts the story of the FBI’s surveillance against King, and how what began as part of their anti-communist mission transformed into an almost personal vendetta. The FBI’s surveillance of King started when in 1962 the FBI learned of his association with Stanley Levison, a Jewish attorney who was one of King’s most important advisors and who at one point during the 1950s had been a supporter of the Communist Party.