Dial "N" for Nerder

"I'd rather have a chubby hubby than a sexy exy."

- Marge Simpson

"Dial 'N' for Nerder" is the fourteenth episode of The Simpsons ' nineteenth season. It originally aired on March 9, 2008. Bart plays a prank on Martin, but by accident, Martin falls down a cliff. Bart and Lisa start to feel guilty and act very suspicious, something that makes Nelson want to investigate. Meanwhile, Marge thinks Homer is cheating on his diet.

Plot
Homer and Marge are in bed about to snuggle. Homer, however, is far too lazy to do so. This prompts an infuriated Marge to make a healthy breakfast consisting entirely of vegetables for Homer the next morning. Marge decides to hire a formerly obese nutritionist named Betsy Bidwell to help with Homer's food addiction. Betsy tells Homer of a simple trick called "substitution". Betsy explains to Homer that he substitute his food, with food that could help him lose weight. Betsy tells Homer to begin eating bell peppers. Homer begins eating the bell peppers everywhere including a baseball game and at Moe's Tavern as a beer smoothie. After Betsy and Marge measure Homer's weight, a shocked Betsy informs Homer that instead of losing weight, he has gained seven pounds. Marge suspects that Homer may have cheated on his diet. While Bart and Lisa are watching television, Marge discovers a show called Sneakers, which purports to investigate people suspected of cheating on their partner. Marge decides to call the producers, with the intention of having them stalk Homer and see if he is cheating on his diet. Marge successfully manages to reach Sneakers, and they decide to help her.

Bart and Lisa decide to tour Springfield National Park. At the top of a mountain, the two discover Martin excavating for arrowheads. While Lisa joins him in excavating, a frustrated Bart decides to play a prank on Martin. Stealing Sideshow Mel's bone (which causes his hair to fall straight), Bart digs it into the ground, where Martin arrives thinking it is a real historic bone. Bart tugs on a string connected to the bone, which causes the bone to fly up and knock Martin in the head. A dizzied Martin tumbles over the edge of the cliff, and falls onto a smaller ledge. Lisa, with the intention of helping him, taps him with a stick, which causes Martin to fall to the very bottom, and is presumed dead. The two arrive home, where Kent Brockman reveals on the news that Chief Wiggum discovered the disappearance of Martin's body. Wiggum informs that when Martin landed, he was eaten by a cougar, which is still coughing up his clothes. Although Bart wants to admit his crime, Lisa, frightened of going to jail for being an accomplice, convinces Bart to deny they were the perpetrators. Homer leaves, claiming he is going to work at 4 o'clock on a Saturday. Marge calls Sneakers and tells them Homer left home, prompting a nearby van full of Sneakers agents to stalk Homer.

At Springfield Elementary School, a memorial is held as a to tribute Martin. Bart begins to panic frantically, thinking someone would investigate. Sure enough, Nelson Muntz realizes that as Martin had a fear of heights, it would be unusual for him to go all the way to the top of a cliff without being lured. Nelson goes up to Mt. Springfield and discovers Sideshow Mel's bone on the string Bart pulled. Meanwhile, the Sneakers agents catch a video of Homer going to a restaurant. Marge confirms her suspicions of Homer cheating on his diet, but realizes that the reality show people do not care about their marriage. She quits the show and embraces Homer, stating that she'd "rather have a chubby hubby than a sexy exy." Bart and Lisa arrive at Martin's greenhouse. Nelson appears and catches Lisa's confession on tape, just as Martin emerges. He recounts how he survived the fall thanks to his underwear with an extra-durable wedgie-proof waistband, and Lisa learns that throughout the entire ordeal, underneath her innocent looking self is a dark twisted person.

Reception
The episode had 7.3 million viewers. It has received pretty positive reviews. Richard Keller of TV Squad quoted "It was a pretty good episode". He went on to say "The addition of Nelson as an investigator to the conspiracy was an interesting move on the producers' part". The Homer sub-plot was "Entertaining and better than the rental car plot he had in The Debarted".