Shock Theater was the final episode of Quantum Leap's third season, also the series' 53rd overall episode. Written by Joe Napolitano, the episode, which was written by Deborah Pratt, premiered on NBC-TV on May 22, 1991.
October 3, 1954: In this episode Sam leaps into a patient in a psychiatric hospital at the moment that a crooked orderly who mistreats patients is about to give him an unauthorized electro shock treatment for punitive reasons. Sam is given a dangerously high voltage shock which wreaks havok with his brain.
When Sam awakens he begins channeling the personalities of people he has lept into over the past three years, including Samantha Stormer, Jesse Tyler, and Jimmy LaMotta which the doctors interpret as signs of multiple personality disorder. Al tries to help Sam get ahold of himself so the doctors will leave him alone so they can complete his mission, teaching another patient who was born with a mild case of Down's Syndrome how to read. Sam, however, believes Al to be an hallucination and refuses to listen to him. Al then takes it upon himself to teach the other patient, who can see Al along with almost every other patient in the hospital, his ABC's with the help of a clever rap song he and Sam programmed into Ziggy as a joke.
After the mission is completed Ziggy theorizes that the only way to get Sam's mind back into a condition that will allow him to leap is to give him a second electro shock treatment equal in voltage to the first. Sam, still in a state of emotional shock from the first treatment, is reticent to comply but is successful in getting the doctors to prep him for a treatment.
Sam, in tears of fear, convinces a nurse to zap him with the same dangerously high voltage which almost killed him the first time and leaps, however a lightning bolt from the storm strikes both Al and Sam. The two suddenly find themselves in the middle of a town square, with Sam returned to normal. They theorize that Al leaped with Sam, but it's clear all is not right... Sam is still wearing his hospital gown while Al is wearing an Army uniform and the handlink is no longer working. They then find out the truth that Al is no longer a hologram while Sam suddenly is the hologram guide, as Al has leaped into 1945, and Sam is back in 1999, in the Imaging chamber!
- Alphabet Rap (performed by Dean Stockwell)