NEW ORLEANS >>  Two Hollywood stars could spend the next two weeks in a New Orleans courtroom rather than on camera, on opposing sides in a real-life legal drama.

Jury selection was scheduled Monday for Stephen Baldwin’s federal lawsuit against fellow actor Kevin Costner over their investments in a device BP used in trying to clean up the huge Gulf of Mexico oil spill.

Both are expected to testify. U.S. District Judge Martin Feldman ruled last month that every litigant must be in court every day “because of the seriousness of the claims and issues raised by the parties” and in case of mid-trial settlement talks.

The federal lawsuit claims Costner and a business partner duped Baldwin and a friend out of their shares of an $18 million deal for BP to buy oil-separating centrifuges after the April 2010 spill.

Baldwin and his friend, Spyridon Contogouris, said they didn’t know about the deal when they agreed to sell their shares of Ocean Therapy Solutions, a company that marketed the centrifuges to BP, for $1.4 million and $500,000, respectively.

BP ordered 32 of the centrifuges, which separate oil from water, and deployed a few of the devices on a barge in June 2010. BP capped its blown-out Macondo well the following month and kept more oil from leaking until the well was permanently sealed in September 2010.

Baldwin and Contogouris claim they were deliberately excluded from a June 8 meeting between Costner, his business partner Patrick Smith and BP executive Doug Suttles, who agreed to make an $18 million deposit on a $52 million order for the 32 devices, according to the lawsuit.

Later that month, Costner and Suttles visited Port Fourchon, La., to talk about the plan to use the centrifuges.

“It was designed to give us a fighting chance, to fight back the oil before it got us by the throat,” Costner said at the time.

Baldwin and Contogouris say they were entitled to shares of BP’s deposit. Their lawsuit claims Costner and Smith schemed to use BP’s deposit buy their shares in Ocean Therapy Solutions.

“The source of the funds to buy plaintiffs’ interest was never disclosed to them, and OTS funds were secretly and improperly converted to effect the purchase,” a plaintiffs’ summary of the case says.

Costner said he didn’t attend a June 6, 2010, meeting at which Contogouris agreed to sell his OTS interests.

“Not only did Costner not know that Plaintiffs were negotiating to sell their OTS interests, he was surprised and offended by the idea that Contogouris and Baldwin would walk away from OTS with almost $2 million in cash despite having invested no money in the company, and at a time when a contract with BP was uncertain to materialize,” says a court filing summarizing Costner’s version of events.

Baldwin and Contogouris are seeking more than $21 million in damages. Costner and other defendants also are seeking damages in counterclaims.