*Warning this post contains The Masked Singer reveal spoilers*

The Masked Singer is one of Fox's biggest hits. Celebrities appear on the show wearing elaborate masks and costumes while they perform hit songs. A panel of celebrities including singer-songwriter Robin Thicke, television personality Jenny McCarthy, actor and comedian Ken Jeong, and recording artist Nicole Scherzinger along with the audience at home try to guess who's behind the mask.

Not only do the audience and celebrity panelists not know the identity of the masked singers, but crew members and even host Nick Cannon are kept in the dark in hopes of preventing any clues from leaking to the public. Last night Leopard was sent home after performing the Shirley Bassey classic “Big Spender” in the final performance.

Leopard was eventually unmasked when it was revealed he would be going home and many were shocked (and some not so surprised) to find out that it was British singer Seal behind the feline mask.

While most of the crowd and panelists had no clue it was the "Kiss From A Rose" crooner behind the mask, even more surprising was that his own children didn't know he was appearing on the show.  The singer shares four children with his ex-wife, supermodel Heidi Klum. “Leopard wanted to do the show because he wanted to surprise his kids. They still didn’t know that he was on when the episode reveal aired,” showrunner and executive producer Izzie Pick Ibarra told Variety.

“He did the whole thing to surprise his kids and make them laugh,” Ibarra said. “I really wanted to send a camera, the moment that his kids see that it’s him, but we couldn’t, unfortunately, for various reasons.”

Ibarra went on to explain that when a performer agrees to appear on the show, NDA's must be signed by anyone they think they may want to tell, and it must be kept a secret from everyone else. “No one else is allowed, unless they’ve been pre-approved with an NDA, so it’s not like they can bring people in-and-out of the production,” Ibarra explained. “We encourage them to not tell as many people as they can. We tell them not to tell their kids a lot because it’s hard for kids to keep secrets, and it’s not really fair of them, obviously — when you are 7 or 8 years old, you don’t necessarily understand not telling people something.”

Ibarra also added that the show goes to great lengths to keep their masked singer's identities a secret by going through special training. “We try to hide their natural body language and mannerisms that they make, so we give them different mannerisms that they work with,” Ibarra explains.

Did you guess that Seal was Leopard?

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