The hit reality singing competition from Fox, "The Masked Singer," has added its own twist to singing contests. Its elaborate costumes, made by the Emmy Award-winning Marina Toybina, has become a foundation for the show's success.

Moreover, with voice changers during interviews, and extensive non-disclosure agreements, it is basically impossible to guess the guests beforehand. One clue is available to the audience, and its mainstay panelists - Ken Jeong, Jenny McCarthy, Nicole Scherzinger, and Robin Thicke. Every week, the masked singers perform a cover of popular songs.

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However, while most artists have their signature vocal quality, there are still instances where everyone is thrown off the hit tv series. To relive the fun of not knowing who the masked celebrity is, here are three of the most surprising "The Masked Singer" reveals.

Season 3: The Swan

While she lasted for only two weeks after being introduced in the middle of "The Masked Singer" Season 3, she was among the season's surprise reveals. The Swan sported a ballerina outfit with her white tutu-like costume and stockings. Her head is a swan with an ice crown on top of it.

She gave off an electrifying performance of Peggy Lee's 1958 hit "Fever." After her lauded cover of "Fever," the Swan said on her next appearance: "Before my last performance, I was petrified, afraid to stick my long neck out. But I pushed past the nerves and dove in headfirst."

During the seventh week, she was voted and was unmasked. However, none of the four panelists and their guest were able to deduce "The Masked Singer." The guesses were as follows:

  • Robin Thicke: Nina Dobrev
  • Jenny McCarthy: Kristen Stewart
  • Ken Jeong: Olivia Munn
  • Nicole Scherzinger: Mila Kunis
  • Guest Panelist Joel McHale: Megan Fox

The Swan actually was actress, model, and artist Bella Thorne. The clues in her package alluded to her previous roles - the shaking thermos was from her Disney Channel's "Shake It Up," the big inflatable heart was for her "Big Love" role, and the screaming was a hint in her appearance in the Scream MTV series. Listen to Bella Thorne's cover of "Fever" below:

 

Season 2: The Thingamajig

The Thingamajig appeared on "The Masked Singer" Season 2, with his plaid suit and green furry monster head with eyeglasses. Describing himself as a "gentle giant, the feathery kind!" the Thingamajig first teased audiences by telling everyone to "keep up the pace."

He has swooned panelists and audiences alike with his strong vocals. He first sang "Easy" by The Commodores, following it up by Kacey Musgraves' heartwarming "Rainbow." The incredibly tall contestant sang John Legend's "Ordinary People" with ease. He later performed Bing Crosby's Winter Wonderland. When it was time to guess, only Ken Jeong managed to get the right answer:

  • Robin Thicke: Montell Jordan
  • Jenny McCarthy: Paul George
  • Ken Jeong: Victor Oladipo
  • Nicole Scherziner: Markelle Fultz

At 27 years old at the time, it was the Thingamajig that was the youngest male constant to join "The Masked Singer." He is none other than NBA superstar Victor Oladipo of the Indiana Pacer. Listen to Oladipo effortlessly belt "Easy" below:

 

Season 1: The Monster

Looking like a cute mix between Monster Inc's Mike and Sully. The Monster said in his intro that it was how "the world labeled me." He said that he was at the top of the game, and that it turned on him.

During his appearances in the first season, his performances include Queen's "Don't Stop Me Now" and Sam Smith's "Stay With Me." In the Season 1 finale, none of the judges even came close to the right answer. Their guesses were as follows:

  • Robin Thicke: Jamie Foxx
  • Jenny McCarthy: Michael Vick
  • Ken Jeong: Darius Rucker
  • Nicole Scherzinger: CeeLo Green
  • Guest Panelist Kenan Thompson: Tyrese Gibson

Once unmasked, everyone was in shock. It was rapper T-Pain who was The Monster all along. He was also the first winner of "The Masked Singer." While T-Pain is among the world's biggest hip-hop artists, most of us only hear his tracks through his autotuned vocals. The artist, Faheem Rasheed Najm, once surprised the world when he did a Tiny Desk concert for NPR. He sang his hits "Buy U A Drank (Shawty Snappin)" minus the autotune, crashing the Internet with his soulful crooner voice.

Listen to T-Pain singing without his signature autotune below: