Each season of UCB has a running joke that culminates in the season's final episode. The skits will make passing reference to the running joke in each episode of that season. For example: the first season's running joke was the Titte Brothers, a fictional pair of performers. They appear in the last episode of the first season when they perform a charity concert for the Little Donny Foundation. The second season's joke was Supercool, a highly-addictive sugar candy. The second-season finale focused on the Supercool smuggling ring headed by the UCB. The third season's running joke was Pro Thunderball, a hyper-violent sport that combines football and baseball. The third-season finale is a mock-documentary of the evolution of Pro Thunderball.