Santa's Little Helper of their sacrifices and starts treating him badly, causing him to run away. He ends up in the possession of Mr. Burns, who trains him to become a vicious attack dog. Several days later, Bart stumbles upon the trained Santa's Little Helper and is attacked, but the greyhound eventually recognizes his old friend and stops. In "The Canine Mutiny" (season eight, 1997), Bart uses a fake charge card to buy a well-trained rough collie named Laddie from a mail-order catalog. Laddie learns many tricks that Santa's Little Helper is completely unable to perform, and the Simpson family nearly forgets about
The Simpsons show. The celebration ended on January 10, 2010 (almost 20 years after "Bart the Genius" aired on January 14, 1990), with "The Simpsons 20th Anniversary Special – In 3-D! On Ice!", a documentary special by documentary filmmaker Morgan Spurlock that examines the "cultural phenomenon of "The Simpsons"". As of the twenty-first season (2009–2010), "The Simpsons" became the longest-running American scripted primetime television series, having surpassed "Gunsmoke". On April 29, 2018, "The Simpsons" also surpassed "Gunsmoke"s 635-episode count with the episode "Forgive and Regret." "The Simpsons" has won dozens of awards since it debuted as a series, including 31 Primetime Emmy