Mariah Carey unveils new single 'Almost Home' - listen

Mariah Carey's new single 'Almost Home' has leaked online in full.

The track appears on the soundtrack of Disney's Oz the Great and Powerful.

'Almost Home' is produced by Stargate and will be released on iTunes tomorrow (February 19).

Oz the Great and Powerful stars James Franco, Mila Kunis, Michelle Williams and Rachel Weisz, and hits cinemas on March 8.

Artwork for Mariah Carey's 'Almost Home'

A prequel to the story of The Wizard of Oz, the movie is about magician Oscar Diggs (Franco) who ends up in Oz and meets three witches (Kunis, Williams and Weisz), who all believe he is the wizard of their dreams.

Carey is currently a judge on American Idol alongside Nicki Minaj, Keith Urban and show veteran Randy Jackson.

Watch a trailer for Oz the Great and Powerful below:

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