In a new track that surfaced online on Monday (November 29) called "Castle Walls" and featuring
"See with the Phantoms and Ferraris in the driveway/ But you see it came in exchange of a sane man's sanity," he raps over the Alex da Kid-produced number. "Your vision jaded by the Grammys on the mantlepiece/ Just switch your camera lenses, you will see the agony."
Aguilera provides a moving chorus to the track as she sings, "If I should tumble, if I should fall/ Would anyone hear me, screaming behind these castle walls?"
Earlier this month, Alex da Kid (Eminem, B.o.B) told MTV News the track would be T.I.'s next single. "I love it," he said of the number. "I think it's amazing. It's my sound, just kind of an evolution of that. I think it'll cater to a lot of different people."
The track will be featured on T.I.'s forthcoming album No Mercy, set to arrive December 7.
The album was previously slated to be titled King Uncaged, but the Atlanta MC changed the name after he was arrested in Los Angeles last month on drug charges and sentenced to 11 months in prison.