Joaquin Phoenix stars as Larry "Doc" Sportello, a pot-smoking private eye at the tail end of the psychedelic '60s who investigates a kidnapping case involving his old flame Shasta Fay Hepworth (Katherine Waterston) and her missing sugar daddy Mickey Wolfmann (Eric Roberts), a powerful real-estate mogul. In the course of his investigation Doc butts heads with Lt. Det. Christian F. "Bigfoot" Bjornsen (Josh Brolin), a part-time actor with a palpable disdain for the free-love generation, and a reputation for committing civil-rights violations. Later, as clues to Wolfmann's disappearance begin to suggest a conspiracy involving the FBI and a mysterious underworld syndicate known as the Golden Fang, Doc seeks the help of his lawyer Sauncho Smilax, Esq. (Benicio Del Toro) and Deputy D.A. Penny Kimball (Reese Witherspoon). Meanwhile, Doc also agrees to search for Coy Harlingen (Owen Wilson), a reportedly deceased saxophone player who may not be as dead as rumors suggest, and who seems somehow tied to the ongoing Wolfmann investigation.