Netflix delivers the official trailer for the upcoming Errol Morris documentary Wormwood, which uncovers the truth behind the C.I.A. and alleged LSD testing.

The six-part series is centered around the C.I.A.’s shadowy MK Ultra program during the 1950s to the early ’70s, where the agency is said to have performed illegal mind control experiments on human subjects, some involving LSD.

It also investigates, in an attempt to uncover the truth about a family story of a man’s 60-year quest to identify the circumstances of his father’s mysterious death, who was among the humans dosed during the experiments.

Wormwood premieres on Netlix December 15.