TOM CRUISE has a naughty secret!

Nearly two years after his divorce from Katie Holmes, the still-single superstar partied at a notorious sex club.

Cruise, 51, thought he’d be celebrating his pal Matt Damon’s birthday at a smart dinner party in London.

Instead, his “Edge of Tomorrow” co-star Emily Blunt revealed that she switched the venue to The Box, a raunchy hangout that boasts a nude emcee, naked dwarf acrobats and lewd sex routines.

“Anything goes at The Box,” a club regular told The ENQUIRER.

“Tom was entertained to the usual mix of naked strip­pers and a transvestite who decorates his private parts with pink lipstick.

“The strippers leave nothing to the imagination, often writh­ing on the stage while rich clients pour champagne over their na­ked bodies.”

British beauty Blunt – who recently gave birth to her first child with hubby John Krasinski, star of TV’s “The Office” – dished on Cruise’s scandalous night out while chatting with late-night host Jimmy Kimmel.

 “I emailed him and was like, ‘Tom, change of plan. We’re now gonna go to this club called The Box. Just wanted you to know you may not be comfortable with this. It’s kinda like a sex club,’ ” Blunt, 31, told Kimmel.

“But being a good sport, Tom was up for anything. He emailed back and went, ‘Well just don’t let me walk out of there alone.’ Which we didn’t.”

The Box is a two-floor palace of decadent luxury hidden behind a plain brown door in London’s seedy Soho district. Guests pay $5,000 for a table on weekends and fork over $100 for the house cocktail, a mix of bourbon and cognac.

Prince Harry, 29, revels in the sleazy antics there, but the owners desperately try to keep the identities of their celebrity clientele secret.

Author Andrew Morton, who wrote the best-seller, “Tom Cruise: An Unauthorized Biogra­phy,” believes the actor’s visit there may be a testa­ment to his love life hitting rock bottom.

“Tom is a guy in need of love,” Morton told The ENQUIRER.

“I think he’s having trouble finding a regular date among the Scientol­ogy clan. But I doubt he’ll have better luck in a sex club where anything goes.”

Cruise’s bawdy night at The Box may also have triggered bitter memories of film­ing the movie, “Eyes Wide Shut,” with his ex-wife Nicole Kidman, Morton added.

“In the film, Tom played a doctor who made a secret visit to an S&M club to take part in a masked orgy,” Morton not­ed.

“It’s the longest continuous shoot in film history, and I be­lieve the strain of making it broke up their marriage.”