The Trip (1967)

Bruce Dern, Dennis Hopper, Peter Fonda, Peter Bogdanovich

Paul Groves (Peter Fonda), a television commercial director, is in the midst of a personality crisis. His wife Sally (Susan Strasberg) has left him and he seeks the help of his friend John (Bruce Dern), a self-styled guru who's an advocate of LSD. Paul asks John to be the guide on his first "trip".