"Dia-BILL-ic Shock" is an episode of King of the Hill. It is the first episode of the thirteenth season, originally aired September 28, 2008. It was written by Sanjay Shah and directed by Ronald Rubio.
In this episode, Bill, after consuming large amounts of sugar at an amusement park, has a blood sugar spike and is diagnosed with diabetes. Hank and his friends do whatever they can to stop Bill from going back to his old habit.
At an amusement park with Hank and Bobby, Bill downs huge amounts of sugary snacks until he passes out from a sugar spike and is taken to the hospital. At the hospital, a doctor diagnoses Bill with diabetes and tells him to stop eating junk food and to work out. Bill doesn't follow his doctors advice and passes out again. At the hospital, a different and mean spirited, egotistical doctor sees Bill as someone who'll never learn and coldly tells him that he will lose his legs and that he should start using a wheelchair. Hank and the others are shocked and saddened when Bill returns to the alley in his wheelchair, and believing this to be a permanent change conspire to remodel Bill's house to make everything in it wheelchair-accessible and help him out however else they can. When Hank takes a downcast Bill to the park, Bill is befriended by a wheelchair rugby player nicknamed Thunder, a sports enthusiast with whom Bill finds camaraderie, who teaches him that he can still be independent despite being wheelchair-bound.
After Thunder lends Bill his spare rugby chair, Bill takes to the court himself; over time he proves to be a competitive, capable player, and his depression turns to confident delight with his new upper-body strength as earns him respect in others and women find him attractive. However, as the rugby players loudly celebrate one of their games at a bar one night, Bill tipsily excuses himself to use the restroom... and makes his way on foot, impeded only by the beers he'd had. When the other players indignantly protest Bill's 'deception', he attempts to explain that he has diabetes and whips out his blood glucose monitor - only to read normally, as all the exercise from playing rugby had reversed his condition. Thunder and the players quickly ignore him as Bill leaves with him wheelchair. Upon returning home Bill finds that his friends have finished remodeling his house. But when they see that Bill can walk, they get just as angry at Bill as the rugby team was for lying to them and storm off. Things have gone back to the way they have with Bill, as he is no longer confident with himself, people no longer respect him, and women no longer find him attractive.
Distraught by this, Bill consumes large amounts of sugar to put himself back in a diabetic state, but Hank and surprisingly Thunder stop him. Bill tells them he wants to be diabetic again because his struggle will make him an inspiration. Thunder (who has been told of Bill's plight by Hank) sets Bill straight by reminding him of everything he did with the team: Diet, exercise, and activeness, allowing Bill to cure himself and doing that is inspirational. Thunder says if he was bill the first thing he would do with his legs would be to stand and confront the doctor who misled him. Following Thunder's advice, Hank and Bill meet up with the rude doctor as Bill reveals to the man that he's cured. He backs the now scared Doctor into a room, saying that his legs work fine as he proceeds to beat the doctor up, while a nurse (whom the rude doctor had insulted earlier) turns a blind eye to the beating as Hank waits for his friend to finish.
- The scene in which Bill is playing basketball with the Rugby team, the song playing is "I'm Shipping Up to Boston". The song says that the man is going to lose his legs, just like Bill thought he would do.
- "For Your Own Again" by Steve Lang can also be heard while Bill and Thunder were at a club.
- When Bill returns to the hospital in the final scene, nameplates of doctors on doors read "Dr. Lawrence Fine, D.D.S." and "Dr. Moe Howard," referring to Moe and Larry from The Three Stooges.
- This is the first time in the series that a main character is diagnosed with Diabetes.
- Dale mentions Winnie the Pooh has the same way Bill has diabetes.
- This marks a rare time where Bill wins as he beats up his rude doctor.
- Glucometers do not display the word "normal;" instead they show the amount of serum glucose in a numerical value.