The episode: “Gamera vs. Gaos,” ep. 308
The riff: Said in an oddly stilted tone by Tom after a journalist tailing after a kid calls to him, saying “Boy, boy…”
The explanation: This is a clever reference to Leonard Bernstein’s song “Cool” from “West Side Story.” In the original musical, it is sung by Riff as he gets the Jets ready for their showdown with the Sharks. In the film, the context is changed because the song is sung after Riff has been killed. Now it is repurposed to tell the Jets they need to “be cool” and not do anything rash in their anger. It is often regarded as one of the film’s best choreographed pieces.
Novelty factor: I don’t know “West Side Story” nearly well enough to pick up that small a reference, but I enjoyed reminding myself with the video below.