Homer and Bart learn that Truckasaurus - a giant, fire-breathing mechanical dinosaur made out of trucks - is coming to the Springfield Speedway. Homer proposes that the whole family attend the event, even though it falls on the same night as Lisa's saxophone recital. homer and Bart anxiously sit through the performance and then rush the family to the rally. Entering the speedway arena by mistake, the Simpsons' car is mauled by Truckasaurus.
At the show, Bart is enthralled with the stunts of fearless daredevil Captain Lance Murdock. When Murdock's stunt goes awry, he is pulled from a shark and lion-infested tank to a rousing ovation. Bart knows he has found his calling. Performing his first stunt in front of the local kids, Bart flies off his skateboard and smashes into the pavement. Dr. Hibbert gives him a safety lecture, while Captain Murdock, healing in the hospital, urges Bart to live his life on the edge.
With Murdock's encouragement, Bart decides on the greatest stunt of his life: jumping the Springfield Gorge. Homer concludes that the only way he can stop Bart is to do the stunt himself and show Bart how dangerous it is. He mounts Bart's skateboard, but Bart, knowing Homer will surely die if he tries the stunt, agrees to give up his skateboard career. Homer accidentally rolls backwards down the ramp. Airborne, he feels the elation of flight, but runs out of momentum and crashes into the side of the gorge.
