Inside the $46 million Los Angeles mansion that just sold

Liongate mansion.

It's a mystery owner selling to a mystery buyer. But one thing is certain: The Bel-Air estate called Liongate has just sold for $46 million.

The estate, once owned by Kenny Rogers, was listed last year for $65 million. While the new sale price might seem like a big discount, it's still much higher than the $12.2 million it fetched in 2010, the last time it changed hands.

The listing agent, Mia Trudeau of Hilton & Hyland, declined to identify the buyer or seller. But she gave "Secret Lives of the Super Rich" an exclusive tour of the property just before it was sold.

When Liongate was rebuilt in 2013 the original façade seen here was the only thing salvaged.

"I've shown it about 50 times," Trudeau told CNBC. "I keep getting more and more impressed as I show it, every time I see something new that excites me."

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The house has a glamorous past. It was built in the 1930s by the architect who built homes for Lucille Ball and Frank Sinatra. But starting in 2013, it was rebuilt and enlarged to become a modern megamansion, with 23,000 square feet, including 11 bedrooms, 17 bathrooms, a glass elevator, billiard room and home theater. The master bedroom alone is 3,000 square feet.

When country music star Kenny Rogers lived here in the 1970’s, he installed these lions, and named the house Liongate.

The Los Angeles estate is called Liongate for the pair of statuary lions guarding the gate.

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The house was offered completely furnished—along with all the art and accessories—showing the growing popularity of "turnkey mansions" that allow the rich to move in immediately after buying.

Security is also key to today's rich buyers, especially for the overseas wealthy. The home has 32 cameras, four gates with double-high walls and a panic room in an undisclosed location.

"You would not find it," Trudeau said. "It's hidden away."

So the panic room is a secret—just like the identity of the buyer and seller.

Watch "Secret Lives of the Super Rich" on Tuesday, March 24, at 10 p.m. ET/PT.