From the History Channel web site:
Plant Explorer Richard Evans Schulte’s discoveries of hallucinogenic plants revolutionized science and laid the foundation for the psychedelic sixties. Now his protÃ©gÃ©, Wade Davis, follows in his footsteps to experience for himself the discoveries that Schultes brought to the western world. Watch native ceremonies and visit laboratories in Switzerland to explore the evolution of psychedelic substances from sacred plants to LSD. Join legendary authors, musicians and Beat Poets on an epic journey that spans decades.
(all times Eastern)
Saturday, April 19 10:00 PM
Sunday, April 20 02:00 AM
Saturday, April 26 05:00 PM
According to this post on DeadNet, Bob Weir appears in the documentary, and some Grateful Dead music is included.
View the trailer here.