In modern-day New York City, John the Baptist calls out to a group of young men and women to learn from the teachings of Jesus. Through song and dance, they relive Christ's crucifixion.
The well-known explorer and hunter Captain Spaulding has just returned from Africa, and is being welcomed home with a lavish party at the estate of influential society matron Mrs. Rittenhouse when a valuable painting goes missing. The intrepid Captain Spaulding attempts to solve the crime with the help of his silly secretary Horatio Jamison, while sparring with the anarchic Signor Emanuel Ravelli and his nutty sidekick The Professor.
From an ominous Lecturer, a small 1930s middle American community learns of the Harper Affair, in which young Jimmy Harper finds his life of promise turn into a life of debauchery and murder thanks to the new drug menace marijuana. Along the way, he receives help from his girlfriend Mary and Jesus Himself, but always finds himself in the arms of the Reefer Man and the rest of the denizens of the Reefer Den.