Following the sudden firing of drummer Joey Castillo, Foo Fighters frontman (and former QOTSA drummer) Dave Grohl handled percussion duties on a number of songs. The album also boasts appearances from Alex Turner of the Arctic Monkeys, Trent Reznor of Nine Inch Nails, the band's former bassist Nick Oliveri, and Sir Elton John, who plays piano on the song "Fairweather Friends."

The collaborations, many of them with familiar faces, start to take on a different meaning when one knows the back story: Frontman Josh Homme had a near-death experience during routine knee surgery before the band went to work on the album. When asked if the cameos were a way of surrounding himself with friends, Homme replied, "Yes, absolutely."

"It dawned on me after we did the first interview [for the new album], people were so kind of like entranced by the marquee value of all these [guest artists]," Homme told Radio.com. "I didn't think about that, you know? We forget that for you it's Dave Grohl, Nick Oliveri, Alex Turner, but for us it's just Dave, Nick and Alex. There comes a time when you need your friends, and so you call them. You don't really know somebody until everything around you goes wrong. So what was great was to realize in these tougher moments who is really there."