Up in Smoke is essentially a drawn-out version of the drug-oriented comedy routines of Tommy Chong and Cheech Marin.
Script by the two comedians has hippie rich kid Chong teaming up with barrio boy Cheech in a confused search for some pot to puff on, presumably to aid them in putting together a rock band. Pursuit takes them to Tijuana, where they end up driving back a van constructed out of treated marijuana called ‘fibreweed’.
In diligent pursuit is narcotics detective Stacy Keach, saddled with the usual crew of incompetent assistants. The trail eventually leads to popular LA nitery, The Roxy, (in which Adler is partnered) where the dopers’ band engages in a punk rock marathon. They take top prize when the high-grade van, catching on fire, inundates the club with potent smoke.
What’s lacking in Up in Smoke is a cohesiveness in both humor and characterization. Once the more obvious drug jokes are exhausted, director Lou Adler lets the film degenerate into a mixture of fitful slapstick and toilet humor.