Demi Lovato surprises fans on The Masked Singer

Demi Lovato shocked fans when she was unveiled on The Masked Singer on Sunday night.

The Confident hitmaker, who uses they/them and she/her pronouns, performed What About Love by Heart in their Anonymouse disguise, a giant mouse wearing a spiky leather jacket and gothic red dress.

Judges Nicole Scherzinger, Robin Thicke and Jenny McCarthy correctly guessed that Anonymouse was Demi before she was unmasked, while Ken Jeong incorrectly guessed Lady Gaga.

After they took off the giant mouse head, host Nick Cannon yelled, "Oh my god, the amazing Demi Lovato. One of the biggest stars in the world. Two-time Grammy nominated multi-platinum sensation. Wow!"

He asked the judges how they knew it was Demi and Jenny said, "That voice," and Robin added, "You are one of the great voices and talents of any generation."

After the reveal, the 31-year-old told Nick, "I wanted to do your show because it seemed so fun. And it has been so fun. And I get to sing, so it's the best of both worlds."

She later added, "This has been so much fun. Your words are so kind and I took them to heart. So thank you. And the energy from this audience is so great!"

Demi was the only mystery guest on the special episode, which celebrated the show's history ahead of its season 10 premiere later this month.

The singer is gearing up to release Revamped, an album filled with rock versions of her pop songs, on Friday. They will perform at the MTV Video Music Awards on Tuesday.