All Nightmare Long

Singer James Hetfield revealed to Jam! Music that the chorus is a leftover from Metallica's 2003 album St. Anger.

Hetfield explained to Jam! Music that lyrically, "it was an attempt to get back to the H.P. Lovecraft mythos with 'Thing That Should Not Be,' 'The Call Of Ktulu.' This was about the hounds of Tindalos, which was another crazy mindf--k about these wolves that hunt through their nightmares and the only way you can get away from them is stay with angels. You can't even escape through sleep."

In an interview with Artist Direct, the interviewer commented that he felt this song was saying that death is always chasing us, and we're always running away from it. However, it's still pulling us. Bassist Robert Trujillo agreed with the statement and added: "It's a constant chase. We've all had dreams where something is chasing us. Whatever monster that is... it could be someone's addictions, or it could literally be that chase sequence in your dream where you're on the tour bus and you're floating over the edge. You look down and you see nothing but rocks and water, which is a dream that I've had plenty of times. It's very interesting. The music has a lot of imagery to it. You can close your eyes, put on your headphones and see things. It's pretty cool. That, to me, is a sign of something special. This album took time, and there's a lot of detail. Metallica's a band of detail. Everybody knows that. Things take time because people like James are very thorough. He explores a lot of possibilities with the lyrics, the lyrical format and the arrangements. There is tons of detail to it."