When Julian describes the neighbor Barclay as being "richer than Crassus," it’s a meta-joke: Simon Farnaby (who plays the ghost Julian) famously played Crassus in the Horrible Histories series.
Just as Monica Geller turns off the lamp at the end of the Friends theme song, the episode ends with Robin using his powers to turn off the light. [S1E5] Moonah Ston
It is revealed that the grounds of Button House were once a sacred site that Stonehenge was actually copied from. When Julian describes the neighbor Barclay as being
Are you interested in learning more about or other pop culture references hidden in the show? "Ghosts" Moonah Ston (TV Episode 2019) - IMDb Are you interested in learning more about or
The ghosts become obsessed with Friends after watching it on Mike and Alison's TV. Throughout the episode, Thomas attempts to use Joey Tribbiani’s famous catchphrase, "How you doin'?" , while Julian references a "bank account in Fiji"—a nod to Chandler Bing.
The title is the caveman ghost Robin's pronunciation of "Moon Stone".
In a tribute to the Friends opening credits, the episode concludes with Mike and Alison moving a sofa outside so Robin can watch the lunar eclipse. The ghosts sit on the sofa in a formation that mirrors the Friends cast in front of the fountain.