Radioactive Man is fighting crime with his dog until Dr. Nick walks in. It's really a commercial for a pet show, and Nick's hosting it. Bart Simpson wants to take Santa's Little Helper there, and when he does, there's a huge line full of Springfield's citizens and their pets. Before Bart goes on, it shows acts with characters such as Gil or Milhouse Van Houten doing acts with their pets (Milhouse has a muskrat, and Gil has a frog). Bart finally goes on with Santa's Little Helper doing impersonations, but a huge animal brawl breaks out. Santa's Little Helper escapes and goes to a nearby Krusty Burger, where Krusty the Clown is making a new commercial. As he's doing the commercial live, Santa's Little Helper comes in and bites Krusty's butt, causing him to yell loudly. Bart soon finds his dog, and, without realizing it, signs a contract that Santa's Little Helper can be in more commercials and merchandise, and gives it to SLH's new agent, Nigel. SLH and Krusty start showing up everywhere, to T-shirts to coffee mugs to Saturday Night Live. Bart misses SLH, and Nigel gives the family a "pet divorce video", where he mimics SLH's voice into English. Bart is soon mad at Nigel, and goes out to get SLH in a court case which the Simpsons lose. He, after that, sees a movie commercial starring Rainier Wolfcastle, which SLH has a cameo in. Bart goes to the nearby studio, and Nigel refuses to let him go- and says that if he goes near a tempting steak by Nigel or Bart, whoever wins who he goes to will keep him. He goes to Nigel, and after Bart is sad and leaves, Nigel is cruel to SLH and the dog chokes on a paid Krusty Burger. After SLH realizes the cruelity, he goes back home to Bart.