Paulo Costanzo and Mark Feuerstein

It's always sunny in the Hamptons on USA's beachside medical drama Royal Pains. But for Season 3, premiering Wednesday at 9/8c, there are a few clouds on the horizon for brothers, best friends and business partners Hank (Mark Feuerstein) and Evan Lawson (Paulo Costanzo). "I know from the writers that it's going to a potentially dark place between the brothers," Feuerstein tells TVGuide.com.

Whereas the return of their long-lost father, Eddie R. Lawson (Henry Winkler) last season brought up minor differences between the siblings, this time it's HankMed that's causing problems. "Like with so many companies that are owned by families or brothers, there can be tension about where to take the company," Feuerstein says. "Hank and Evan have very different ideas."

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Possibly making matters worse is Evan's deepening romance with his girlfriend, Paige (Brooke D'Orsay). "There are some complications in that relationship, and particularly with Paige, that remain a mystery to me even, but that make her questionable for him and that also provides another conflict for Hank and Evan," Feuerstein says. "By the end of the summer season, and certainly by the end of the winter season, you'll find that Hank and Evan will have gone through something very intense."

Feuerstein knows the conflict between the show's central pair is something viewers "never want to see," but believes the long-term payoff is worth it. "That's a risk that I think the writers are willing to take because it will only challenge our viewers and deepen our relationship as brothers," he says. "All of the storylines and all of the arcs for the characters take them deeper and into new dimensions of the characters that we haven't seen."

So what else is coming up for the Hamptons' top concierge doctor? Read on!

Royal Pains: Ed Asner to play Hank and Evan's grandfather

1. The rest of the family is as dysfunctional as ever: To add to the brewing tension between Hank and Evan is their growing concern for jailbird father, Eddie. The Season 2 finale saw Eddie turn himself in and begin his time in the big house, but the real test will come once his sentence is over. "Now the question is, when he gets out, will he be able to walk the straight and narrow path?" Feuerstein says.

Although Eddie is down in Florida, the Lawson brothers will leave the Hamptons behind to make a trip down south, where they'll also meet their grandfather, played by Emmy winner Ed Asner. "Not only was our father estranged from us but — like father, like son — our grandfather was estranged from our father for many, many years because Eddie decided to marry the woman that became our mother," Feuerstein says. "So there's a lot of conflict in the Lawson family."

2. Expect to see a completely new Hank (at least for a few minutes): After a long winter in the Hamptons, fans may not immediately recognize Hank thanks to his new beard! Feuerstein says it took seven weeks to grow out the new look although, sadly, the whiskers only make a brief cameo. "My wife actually likes the beard. She thinks I should have a beard more often," he says with a laugh. "I'm thrilled not to have a beard because it couldn't be more itchy."

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3. Hank and Jill still can't make it work: Don't worry, Jank fans! Jill (Jill Flint) will return from her globetrotting adventures, but don't expect things to just go back to normal. "It was the first time she left the Hamptons and now, she sees that she can not only survive on her own in another part of the world, but she can thrive and help other people," Feuerstein says. "She comes back a more experienced, less innocent Jill and she's feeling like perhaps other parts of the world are calling her away from the Hamptons, away from the small-town life. Things are not boding so well for Hank and Jill."

4. ....Not that there's anything wrong with that: In the grand tradition of will-they-won't-they couples like Ross and Rachel and Sam and Diane, Feuerstein says he's fine with keeping the two apart for now. "You wait until a series has had its full run of its story lines before you close a significant romance like Hank and Jill," he explains. "I hope they keep it alive, but they do so in a way that isn't unbelievable and which can somehow stretch over 10 seasons." Plus, keeping Hank single has its advantages, like mild flirtations with upcoming female guest stars such as Natalie Zea and Shiri Appleby. "By keeping Hank available there may be more opportunities for the writers to tell different stories," he says. "It never plays out because I think the writers want to be careful about who they introduce and how many romantic interests they ever introduce."

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5. Art will intimate life for Feuerstein: The second episode of Season 3 will not only see Feuerstein hit the football field with recent Super Bowl champ Greg Jennings of the Green Bay Packers, but also with his longtime friend and real-life high school football rival Michael B. Silver (NYPD Blue). Keeping true to form, Silver will play Hank's rival, Ken "Killer" Keller. "It was great because there we were like we had been in high school, on a football field racing against each other, pounding into each other," he says. "It is no way acting because we are truly going head-to-head, trying to clobber each other on every play and in every scene."

Watch an exclusive clip from the Season 3 premiere: