Demi Lovato Records Mystery Duet

Demi Lovato has hit the studio with a mystery man!

The 21-year-old singer teased fans yesterday when she tweeted a photo of her hand giving a thumbs-up next to another thumbs-up with the message that she had just finished recording a duet. But who does the second thumb belong to?

So far there are a couple of contenders. Demi’s uppercase “KILLER” could be a hint that the hand belongs to Brandon Flowers of the Killers. Who doesn’t love a cryptic tweet with a pun, right?

Or maybe the thumb belongs to Nick Jonas! Demi and the former Jonas Brother have had a long-term working relationship, so it wouldn’t be all that surprising. Plus, fans-turned-detectives pointed out that the duet hand in the Twitter photo is wearing a gray suit and white shirt, which just happens to be the outfit that Nick had been seen sporting earlier in the day.