Fortress

This mellow track was written by QOTSA frontman Josh Homme for his daughter Camille and sons Orrin and Wolf. He told The Sun: "I want to make someone misty-eyed, then I want to see them happy. I want that spectrum." "That track is a big deal," he added. "One day when my kids are older, they'll understand it and will have it when I'm gone. Music takes on a life even when you're not here."

A tipsy Dave Grohl turned up at the studio just as Homme was struggling with a vocal take for this song. The importance of getting the vocal right on the highly personal track saw producer Mark Ronson take charge and evict Homme's pal. "I didn't see it because I was [in the studio] wrestling an alligator, but in this case Ronson is the new guy and he was very sweet and was protecting me", the QOTSA singer said. "Maybe in his own mind he thought he was protecting Dave too."

This is an unusually mellow song for QOTSA. Guitarist Troy Van Leeuwen told Uncut: "It's really delicate for us to venture into that territory; they need to have the right lyrics or it turns a bit soppy. We're not usually a ballad band, but musically we can do anything we want."