Last year's The Masked Singer winner Nicola Roberts accidentally exposed the identity of Robobunny after she did a duet with the unknown celebrity.
The former Girls Aloud, 36, was asked by presenter Joel Dommett if she "had any idea who she was dueting with" - and surprisingly, she said yes.
Spilling some secrets, Nicola said: "I haven't been told, but I know who it is."
The judges were in shock, with Rita Ora begging her to tell more.
Davina then quizzed her: "How do you know?" as Nicola continued: "He sang four words and I was like, 'Oh my God!' I'm not gonna make it easy for you, you have to guess."
"Tell us, tell us!" Davina begged.
The judges speculated it was Mark Feehily from Westlife, to which Nicola responded: "All of my childhood dreams came true."
Robobunny was then later unmasked as Mark, which fans were so excited about.
One person wrote: "Feel like my teenage self again, watching IOU in Merville, mesmerised by mark feehily’s voice! What a lovely, humble guy #MARK @MarkusFeehily #Robobunny."
A second commented: "ROBOBUNNY: THIS. IS. MARK!! I have grown up listening to Westlife and this is undeniably him... American accent is fake BUT the Irish is slipping in when he’s said ‘thought’ and a few times when singing."
Many fans argued Mark should have won the competition over Panda - who was crowned this year's winner.
One infuriated fan penned: "Omg come on! Robobunny was way better! Mark from Westlife doing multiple voices! And you give it to some has been! Have a day off! Massive anti climax! #TheMaskedSinger #maskedsinger #maskedsingeruk #themaskedsingerUK."
Another fumed: "Not quite sure how Panda won over Robobunny or Mushroom, but oh well. Guessed them all tonight - such a stupid but fun show #MaskedSingerUK."
Natalie Imbruglia was unmasked as Panda on tonight and crowned champion of the ITV singing competition.
The singer-songwriter and Neighbours actress was revealed to be underneath the cuddly costume on the ITV guessing game during the show's final episode, taking home the victor's gong for 2022.
The finale of the singing battle welcomed back contestants from the first two series, including last year’s winner Joss Stone, who was unmasked as Sausage in 2021.
Do you have a story to sell? Get in touch with us at webcelebs@trinitymirror.com or call us direct 0207 29 33033.