The Simpsons: Lisa's Date with Density

"Lisa's Date with Density" is the seventh episode of season eight of the animated comedy series The Simpsons and the 155th episode of the series overall. It was directed by Steven Dean Moore and written by Reid Harrison. It first aired on the FOX Network on December 15th, 1996. In this episode, Leonard Nimoy tells the tale of a near alien encounter, which takes place in the town of Springfield when Homer Simpson drunkenly leaves Moe's Tavern late at night and allegedly witnesses a glowing green alien. The FBI send their top agents to investigate, Fox Mulder and Dana Scully.