Die Käfer are a fictional band from the videogame series Wolfenstein. In The New Order and The New Colossus, you can find vinyl records with some of their songs on them, and listen to them in the collectibles menu. The band are a parody of Liverpool rock band The Beatles; Die Käfer means “The Beetles” in German.

In-game bio:
“When Die Käfer was formed by four Englishmen from Liverpool in Nazi-controlled Great Britain, they were faced with a choice: either start singing in German or face banning and detainment by the Nazi regime. Die Käfer chose to adapt to the times. They changed their name and learned how to sing in German. Currently, they’re touring Europe to promote their latest "Das Blaue U-Boot” album. Rumor has it that they lace their innocuous pop music with hidden codes which subvert the original meanings of the lyrics. "