The Masked Singer judges Davina McCall and Jonathan Ross have said that the introduction of the show's first ever duo act has made their job even harder.

When the popular show returns in the new year, viewers will meet 'Cat and Mouse' - two mystery celebrities, who may or may not be connected to each other, performing as a single act.

"It's funny because you'd think, 'Oh. Well, there's two of them. If they're a duo, then it's easier to guess'," said McCall. "But I've been looking at them thinking 'You're not a couple', but then they might be acting like they are a couple."

Ross added: "So it makes it a bit harder to guess because the clues could be about one of them or both of them, you know what I mean?

"So it's harder in many ways but it's a lot more fun to watch because you try and pick up from them what is their relationship? Are they people who are together off screen? Are they people who work together?

"So it feels like a different element and it means that they can do different things on stage together as well. So you have a different kind of comic dynamic going on there."

The Masked Singer begins at 6.30pm on New Year's Day on ITV1.

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