He performed an emotional rendition of Elvis classic, Can’t Help Falling in Love but dropped some huge clues after the performance.
As Monster was given the opportunity to give away two lies and a truth, he teased more information about his true identity.
He told viewers he has an identical twin, a major hit with DJ Calvin Harris, with the third clue revealing: “I am Cee Lo Green!”
Will Monster make it through to another stage of the ITV show, and is it Cee Lo Green behind the mask?
The Masked Singer continues on Saturday at 7pm