Kyle Howard, Danny Masterson

Royal Pains' Hank and Evan Lawson are about to get some competition in the brotherly love department.

That '70s Show alum Danny Masterson is set to guest-star on the USA series as the brother of returning guest Kyle Howard (My Boys), TVGuide.com has learned exclusively.

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Howard first appeared on Royal Pains as Season 3 as Dr. Paul Van Dyke, a physician at Hamptons Heritage who later joined HankMed as one of Hank's replacements. After Hank rejoined the business, Paul eventually left to start his own concierge practice in Miami. He most recently returned last season.

Paul will come back for the Season 6 finale, but this time as a patient of HankMed's. Masterson will play Paul's brother, Danny Van Dyke, a wealthy hedge fund manager who needs a kidney transplant but is reluctant to accept his brother's organ.

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Howard and Masterson join previously announced guest stars Khloe Kardashian and Scott Disick, who will play themselves in the finale, set to air Sept. 2 at 9/8c.

Since his role as Hyde on That 70's Show, Masterson most recently starred on the TBS sitcom Men At Work. Howard will next star in the new TBS comedy Your Family or Mine.

Royal Pains airs Tuesdays at 9/8c on USA.

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