Songfacts®:

• Queens of the Stone Age frontman Josh Homme sings on both this tune and another AM track, "One For The Road." Homme produced half of Arctic Monkeys' 2009 album Humbug, and vocalist Alex Turner lent backing vocals to QOTSA's ...Like Clockwork track "If I Had A Tail." Turner told BBC Radio 1's Zane Lowe that Homme's appearance on the album was both casual and potentially unusual. "The Josh thing was very much a case of one of us returning a back scratch to the other," he said. "He came down and sort of got us out of a little rut. It's just fun, it's friends, extended family now - [they] came round, had a fun night. His contribution to our record is really exciting, it's probably my favorite. The 30 seconds that he's in there is just, I dunno, it's like something that I've never heard before."
• Turner told NME about Homme's contribution to this song: "I think he sounds a bit like Bowie. It's my favourite bit of the record, that breakdown; that 30 seconds where it all goes weird," he said. "What's most interesting about it is how accidental it was - I'd sung on the new Queens record a few weeks previous, and we were kind of in a rut a little bit, in this dark rooms. So Josh came down, Nick (O'Malley, bass) made cocktails and we just hung out for the night. We got him to sing on 'One For The Road' and then we were playing him 'Knee Socks,' because we'd just been working on it. We were thinking about putting someone on that section, possibly to do the bit that the three of us were originally doing, which is this really fast R&B bit. But then he heard it and then he said, 'I've got this really great idea for a counter-melody background thing,' and he went and did that and it suddenly became this whole other thing that you never excited it to be. I think it kind of makes the tune. Suddenly, we were out of the rut and re-energised - Josh saved the day!"