Lisa the Simpson

Phil Hartman as Troy McClure

"Lisa the Simpson" is the seventeenth episode of The Simpsons' ninth season. It originally aired on the Fox network in the United States on March 8, 1998. In the episode, Lisa fears that she may be genetically predisposed to lose her intelligence after Grandpa tells her of a family gene that can permanently take away intelligence.

"Lisa the Simpson" was written by Ned Goldreyer and directed by Susie Dietter. This episode was the final episode with Bill Oakley and Josh Weinstein as show runners. It received generally positive reviews from critics, and is considered one of the best episodes of the ninth season.

At Springfield Elementary, Lisa is presented with a brain teaser, which she is unable to solve. Following this incident, Lisa finds herself unable to perform simple tasks. Later, Lisa tells Grampa about her recent cognitive problems. He seems to recognize this, and tells Lisa about the "Simpson Gene", which apparently causes all members of the Simpson family to gradually lose their intelligence as they get older.

Meanwhile, Jasper visits the Kwik-E-Mart and attempts to empty the freezer containing ice cream in order to freeze himself, with the intention of being defrosted sometime in the distant future. Apu decides to take advantage of this unusual situation for financial gain. The convenience store becomes more profitable as a tourist trap, until the freezer's cooling system fails, causing Jasper to defrost and walk away.