Jason Isaacs jokingly described Gore Verbinski's new thriller "A Cure For Wellness" as a "roller-coaster ride" crafted by "demented, twisted people."

Best known for his performances in "Peter Pan," "The Patriot" and the "Harry Potter" blockbusters, as well as the TV series "Brotherhood," Isaacs plays the mysterious head of a Swiss Alps health spa where nothing is what it seems in "Wellness."

The film co-stars Mia Goth and Dane DeHaan.

"I thought this clearly had sprung from demented, twisted people and I spoke to Gore on the phone and it turned out a lot worse than I imagined. It looked like the kind of film that would be both fun to be in and deliciously excruciating to watch," Isaacs told UPI during a recent round-table interview with reporters in New York.

"Sometimes it's important that we hold the mirror up to nature and sometimes it's important that we have a big, old roller-coaster ride of emotions when watching a film."

"And watching it last night with an audience for the first time -- having seen the film, I watched the audience -- and they went through all kind of gymnastic aberrations. People were cringing, turning upside-down, they were gripping their partners' hands, they were covering their eyes and looking through [their fingers.] I thought it would be a ride. As, indeed, it turned out to be," Isaacs added.

"A Cure For Wellness" is in theaters now.