'Breaking Dawn's' Nikki Reed 'Nervous' About Soundtrack Duet With Husband Paul McDonald (Video)

Twilight Saga fans already know Nikki Reed as the strikingly beautiful vampire Rosalie Hale, but if they stay for the end credits of Breaking Dawn – Part 2 this weekend, they’ll see -- or hear – a whole different side of the actress.

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Reed and her husband Paul McDonald, who competed on the 10th season of American Idol, appear on the film’s soundtrack with their duet “All I’ve Ever Needed.” The song also was selected by director Bill Condon as the final track to play during the film’s credits.

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“To think that after five films, it’s the last thing you’ll ever hear,” Reed told The Hollywood Reporter. “It’s just really cool.”

The soft track, written by Reed and McDonald “about Bella and Edward, and about each other,” was chosen to balance out the action-packed ending along with Christina Perri’s “A Thousand Years: Part 2,” which plays during the final scene.

“It really gets under your skin, it’s got a great hook,” said Condon of Reed’s song. “At the end, there’s a lot of stuff that happens in this movie, but I like ending on a really poetic feeling.”

Being included in Breaking Dawn 2 is arguably the widest exposure Reed’s music has garnered, but the couple released a well-received duet -- “Now That I’ve Found You” -- this year.

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“Paul and I have … a very strong connection,” said Reed. “It’s easy for us to write love songs together that have a very similar feeling to the film and I think evoke the same emotions.”

The duo performed the track in front of L.A.’s Tent City on Saturday as those camping out ahead of the Breaking Dawn 2 premiere looked on. Said McDonald, “It was Nikki’s first time doing a live show with the monitors and the whole deal. She was like, ‘Oh my gosh! I can’t hear myself,’ and I was like, ‘That’s kinda how it goes when you have no soundtrack – don’t worry about it!'

“I tried to walk her through it, but I think she did a good job,” he added. “She killed it.”

Mr. and Mrs. McDonald also performed the song Monday on CBS' The Late Late Show With Craig Ferguson.

The smooth, piano-backed ballad finds McDonald taking the lead on vocals while Reed lends her sweet voice to the harmony, taking the spotlight as she echoes her husband toward the end.

“My bed sheets feel empty when you’re not home,” they sing. “Your heartbeat helps me sleep, your breath soothes my soul.”

In the climactic chorus, they continue: “Baby, you’re all I’ve ever needed.”

On a track list that also includes Passion Pit, Ellie Goulding, Feist and Green Day, Reed and McDonald’s soothing, sweeping ballad is an undisputed highlight that easily fits with the series’ tonality. In fact, it is perhaps easier to envision Edward and Bella gazing into each other’s eyes as the track plays than it is to picture Reed and McDonald singing it together.

While awaiting fan reaction to the offering, Reed told THR that she was “very nervous” but wanted to show creative fans that she too was inspired by Stephenie Meyer’s epic love story. As for co-star Jackson Rathbone, who also is musically inclined, he doesn’t think his style of music would necessarily fit with the franchise.

“I can’t imagine one of my drinking anthems on the Twilight soundtrack,” he confessed.

For more from the co-stars and Condon, watch the video above.

Email: Sophie.Schillaci@thr.com; Twitter: @SophieSchillaci