>>84 "The Hitchhiker's Guide to the Galaxy" is about the destruction of Earth. The fourth book in the six-book trilogy is "So long, and Thanks for All the Fish". It's the last message dolphins leave after failing to warn humanity about their upcoming annihilation.
https://hitchhikers.fandom.com/wiki/Dolphins >The last ever dolphin message was misinterpreted as a surprisingly sophisticated attempt to do a double backward somersault through a hoop while whistling the "Star Spangled Banner," but was, in fact, a message. >The message was "so long, and thanks for all the fish".
The Hitchhiker's Guide to the Galaxy (2005) references the line in the opening song. It repeats during the end credits. https://youtube.com/watch?v=N_dUmDBfp6k [Embed]
