Isabella's Turn is the rarest of things: a porno with a truly unexpected ending.

It begins normally enough. A busty brunette named Isabella walks into an all-white office room. A sleazy dude with hand tattoos says, "So what brings you here today? You want to be in a pornography movie?"

"Yep, because I like to have sex," Isabella answers. "You know, making a little money off of it isn't so bad either. So why not give it a shot?" Sleazy dude takes photos. The two get naked. Yadda yadda yadda. You know the rest.

It's only when the cameras stop rolling that shit starts to get weird.

See also: This Is How BangBros Made a Porno Featuring a 15-Year-Old Beauty Queen and a Murderer

The skin flick was shot in a warehouse near Miami International Airport on February 13, 2008, and released Valentine's Day (because nothing says romance like anonymous sex). Six years later, it is now at the center of one of the strangest legal battles Miami has ever seen.

This past April 30, the Puerto Rican porn star filed an anonymous, 11-page lawsuit against BangBros.com, the film studio Venetian Productions, and a half-dozen adult film affiliates.

Simply put, Isabella Unknown v. Venetian Productions and BangBros.com et al. is one of the most ingenious legal maneuvers we've ever seen. It's the Miami porn industry's Marbury v. Madison: a lawsuit so devilishly simple it threatens to undermine a multibillion-dollar business.

In her suit, Isabella claims her contract with BangBros is "illegal and unenforceable because the consideration given by Isabella to the Defendants was sexual intercourse outside of marriage, which violates the public policy of the State of Florida." Without a valid contract, the porn -- which is still available online to this day -- is "an invasion of her privacy" for which Isabella is due "restitution."

Translated from legalese: Isabella's contract with BangBros was bogus. Why? Because she was married when she boned for $1,000.

Florida is one of 21 states that still legally prohibit adultery. In the Sunshine State, Statute 798 prescribes up to 60 days in jail and a $500 fine for "any man or woman, married or unmarried, [who] engages in open and gross lewdness and lascivious behavior," although it is almost never enforced.

For the past three years, Florida legislators have proposed overturning the antiquated legislation. In January, Rep. Ritch Workman (R-Melbourne) asked his fellow politicians to "have the intestinal fortitude to repeal what is a ridiculous law."

They didn't. And so Statute 798 remained on the books. Then this April -- a year after the statute of limitations for the lewd and lascivious act expired -- the porn star filed her complaint. Included in the lawsuit is a copy of her contract. Under "description of services," it says simply: "B/G Facial."

Isabella's Turn begins normally enough, but ends with a thorny lawsuitLawrence Metsch, Isabella's attorney, tells New Times he has gone to great lengths to conceal his client's true identity. He says he can't discuss the case because of a confidentiality agreement.

County records show Metsch voluntarily withdrew the suit hours after it was filed, suggesting Isabella received a settlement. Lawyers for BangBros and Venetian Productions did not return requests for comment.

Whether or not Isabella's shrewd legal reach-around paid off, the lawsuit poses problems for Florida's porn industry. As long as adultery remains illegal, what's to stop other porn stars from flashing their wedding rings in court and asking for cash?

Nothing, says UM associate law professor Andrew B. Dawson. In fact, Isabella's lawsuit could open a pandora's box of problems for Florida's porn industry.

"If this were to apply to all adult films, this would not make adult films illegal but would make contracts in this field void," he says. "This would allow the actor to later bring the sort of invasion of privacy allegations as Isabella sought here, since the actor's consent to use of his image for distribution would likewise be void.

"Effectively, it would give the actor the right to seek to stop the film from being distributed (perhaps just to get his image off the internet) or to ask for more money, especially when the video was more profitable than the actor had anticipated," Dawson says.

The adult film industry phrase "money shot" just took on a whole new meaning.

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