This sprawling electro post-punk number builds relentlessly across its nine minutes. Uncut commented to frontman James Murphy that the track is "insane." He responded:
"I played it for my wife and by the back 20 per cent, she was leaning back in her chair: 'That might be too much... 'So I had to remix it and make some space. That song, for a really long time was just the drum at the start, a little percussion and voice, that's all it was. (Then) it just got bonkers. It was a bit of a beast to wrangle."
Lyrically, the song details Murphy's unresolved emotional issues with DFA Records co-founder Tim Goldsworthy. The pair first fell out early in the 21st century when Goldsworthy abruptly left New York to move back to the UK without notifying Murphy. Later, Murphy, another DGA co-founder Jonathan Galkin and DFA sued Goldsworthy for "breach of contract" and "unjust enrichment."
The song title echoes the one of the same name that John Lennon released in 1971 directed at Paul McCartney.
"Sloop John B" is a traditional West Indian folk song, and it was a huge hit for The Beach Boys in 1966. They tweaked the lyric, "This is the worst trip since I've been born" to "...I've ever been on" as a wink to acid culture.