Back at the Reefer Den, Sally drags Jimmy upstairs for a weed-whacked sexual liaison. When Mary arrives looking for Jimmy, the lecherous Ralph is lying in wait. He tries to seduce Mary by tricking her into smoking marijuana herself ("Little Mary Sunshine"). The plan backfires - the power of the weed is so great, it immediately transforms the virginal Mary into a whip-cracking sadomasochist who enslaves the frightened Ralph. Upon discovering Mary and Ralph in a compromising position, a smoke-addled Jimmy attacks Ralph. A scuffle ensues. Jimmy is knocked unconscious and Jack accidentally shoots Mary through the heart. The villainous Jack places the gun in the unconscious Jimmy's hand. Jimmy, who remembers nothing, is convinced that he has murdered his beloved "Juliet". Mary regains consciousness long enough for Jimmy to finally give her his school ring. She dies in his arms ("Mary's Death").