It focuses on the events leading up to and following his controversial death, which the US government originally claimed was a tragic accident, but later admitted was likely a suicide, caused by a mental breakdown brought on after being unknowingly dosed with LSD, while at a meeting with colleagues from the CIA who were involved in Project MKUltra.

Nine days after Olson was covertly dosed with LSD by his CIA supervisor as part of Project MKUltra, he plunged to his death from the window of a hotel room in New York City.

[6] The documentary ends with Eric Olson describing the quest for the truth about his father's death as "Wormwood", having consumed his whole life and with no possibility that any definitive answer, positive or negative, would have released him from the bitterness of the loss anyway.

[12] The New York Times awarded it a NYT Critic's Pick with reviewer A. O. Scott saying "Mr. Morris presents a powerful historical argument in the guise of a beguiling work of cinematic art — and vice versa.

"[5] Matt Zoller Seitz, writing for Vulture.com, "The filmmaking gathers all the bits and pieces of the story together and arranges them in ways that are clever, surprising, and so aggressively (and deliberately) self-conscious that there are times when the whole thing gets close to turning into an intellectualized formal exercise...there’s never a moment where Olson or Morris fail to fascinate.