Jack Nicholson writes this cult drama starring Peter Fonda and Dennis Hopper. TV commercial director Paul Groves (Fonda) is feeling the strain both at work and home following the split from his unfaithful wife Sally (Susan Strasberg). He consults his friend John (Bruce Dern), an advocate of LSD, who suggests Paul take acid to cure his troubles. After agreeing to do so, with the help of his friend Max (Hopper), Paul experiences a mind-blowing trip around L.A.'s Sunset Strip that includes attending his own funeral and meeting a young woman named Glenn (Salli Sachse). But will his night of wild experiences prove constructive?