Earlier this week on Conan, while Conan was speaking to Andy Richter, the subject of George Takei came up in the conversation between the two.
Hearing Takei’s name brought back memories for Conan, who wrote the Marge vs. the Monorail episode of The Simpsons. In Marge vs. the Monorail, Springfield buys a faulty monorail from a conman and Marge has to stop the train from destroying the town.
In the video below, at the 4:21 mark, Conan shared his story of trying to get Takei to appear in the episode and what happened when Takei declined to apppear.
Source: Press Release