Stan Marsh, Kyle Broflovski, Eric Cartman, and Ike Broflovski are seen in Karate class, where the Karate Instructor gets angry at Cartman because he "racks disciprine". After class, a drunk Randy Marsh picks them up. On his way, while trying to pee in a beer bottle, he gets followed by the police. His attempts to get out of the trouble fails miserably, and he gets arrested for drunk driving and gets his license revoked.
Next day in school, a very embarrassed Stan asks Kyle and Cartman to keep quiet about last night's events. However, Randy, who has been sent there by the state, shows up to give a speech about the dangers of drunk driving. After he is done, Mrs. Garrison humiliates Randy for being forced to "go to elementary school classrooms and talk about how pathetic he is", embarrassing Stan even further.
Randy is now obligated to attend Alcoholics Anonymous (AA) meetings for two weeks. The meetings turn out to be religious, making the attendees believe they are powerless to control their drinking and only a higher power can make them quit and that alcoholism is a "disease". Although skeptical at first, Randy easily gets convinced and he is later shown to be drinking more and more at his home and using a wheelchair. Stan, knowing his father is a hypochondriac, tries to convince his father that he only needs to drink less, however, Randy insists that he can only be cured by "a miracle".
In the next scene a Virgin Mary statue is shown bleeding through a hole, its "ass", much to the amazement a priest passing by. Next day lots of people gather around the statue to witness the miracle, some of them with hopes of getting cured of their diseases. After watching the news report, Randy starts to believe that miracle can cure him too. Meanwhile, Stan crashes an AA meeting and asks why they told his dad he had a disease. Having led a cult before, Stan knows what these people really aim to do, however, when he tries to convince them one only needs "disciprine" to quit, he is kicked out.
When Stan arrives home, he notices his dad trying to get into his car to drive to St. Peter's Church. Stan interferes, saying if he gets pulled over for drunk driving again he will be put in jail for ten years. Upon hearing this, Randy demands Stan to drive him to the statue, to which he reluctantly agrees. When they arrive they find themselves in a long line of people in hopes of getting cured of their diseases, like brain cancer and elephantiasis. Randy, who thinks his disease is the worst of all, tries to cut in line, angering the others. With the intervention of an officer whose brother is an alcoholic, he gets to see the statue. The statue spouts a long stream of blood on him. Randy, now convinced that he is cured, gets out of his wheelchair and wows to never drink again.
The next day Randy takes a reluctant Stan to his AA meeting in Whistlin' Willy's. On the news, they see Pope Benedict XVI investigating the statue. The Pope ultimately decides it is not a miracle, given "chicks bleed out their vaginas all the time", so Randy suddenly realizes he was not cured by God and declares himself powerless again. All the other recovering alcoholics follow suit and raid the bar. Randy rushes out of the building with drinks, but Stan catches up. After a long speech he finally succeeds in convincing his father that he was the one in control all along, thus Randy says he will never drink again. However, Stan says that by completely ditching drinking, it would still be controlling his life and that true discipline is moderation. Afterwards, Randy gives his son a piggyback ride home as the sun blazes on the horizon.