Langdon Alger is a Springfield Elementary School student. He is very quiet and enjoys puzzles. Lisa has a brief crush on him, and she shares this with Homer when she is bonding with him while hanging out at the nuclear plant.
- Writer Richard Appel explains on the DVD commentary for "Bart on the Road" that Langdon Alger was the name of a schoolmate of his.
- In the video game Shin Megami Tensei: Strange Journey, some of the official screenshots used in the USA manual name the protagonist Langdon Alger, Lance Murdock, and many other characters from The Simpsons.
- In "Bart on the Road", the character is never actually shown, implying to TV series viewers that he might not actually exist and be something Lisa made up. His appearing in the comics, however, shows that he is indeed real.
- There is a concept album called Following The Lizard Queen by musician Crywank, which was released on Valentines day 2014.
- He looks strikingly similar to Jessica Lovejoy's boyfriend from the end of "Bart's Girlfriend", but it is not explicitly stated whether or not they are the same character.