Brad Pitt's got a Fight Club sequel in the works. His new sparring partner: paparazzi.

The actor's attorney is threatening legal action against any media outlet that publishes photos snapped "surreptitiously" of Pitt, Angelina Jolie and their family, including new twins Knox and Vivienne, on the grounds of their French estate. Jolie and the newborns checked out of the hospital on Saturday, a week after the birth.

In the letter, sent to various publications and available for persual on the Smoking Gun's website, Yael Holtkamp of the high-powered Los Angeles-based law firm Lavely & Singer warns of dire consequences should the images, shot by shutterbugs using "highly powerful telephoto lenses," turn up in print or online.

"The taking of the Photos constitutes a malicious violation of Mr. Pitt's privacy, including under the laws of California and France," the attorney says.

The letter cites one unidentified photo agency that supposedly posted images of the clan lounging on the grounds of the Château Miraval—a sprawling $60 million country manor in the south of France—and has since removed the pics from its website following some persuasion from the Pitt pack.

Holtkamp did not return phone calls seeking comment.

Aside from protecting their privacy, Pitt, 44, and Jolie, 33, have another motivation for clamping down on unauthorized shots.

The supercouple are reportedly negotiating with various publications for the exclusive first (authorized) photos of the newborns. The deal is expected to be worth several million dollars—and if their past track record is any indication, the money will most likely be donated to charity.