Late Thursday night (Dec. 22), Taylor Swift whetted the appetite of her legion fans with news that she has a new song on the soundtrack of the highly-anticipated film adaptation of the blockbuster novel, 'The Hunger Games.'

"Something I've been VERY excited about for a VERY long time is going to be happening VERY soon (and I'm not referring to Christmas)," she tweeted. Later she posted a link to the song, adding: "And this is it, the big surprise... Go get it!"

The moody, acoustic ballad was written with and features the duo Civil Wars. Not long after the surprise link hit the social networking site, #safeandsound became Twitter's top trending topic in the U.S. and No. 2 worldwide.

'Hunger Games,' which is set in a post-apocalyptic world where teens fight to the death in an annual event aired on live television, stars Jennifer Lawrence, Josh Hutcherson and Liam Hemsworth. The film, based on the novel by Suzanne Collins, hits theaters March 23.

Listen to Taylor Swift Ft. the Civil Wars, 'Safe and Sound'

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