BEVERLY HILLS, Calif. — Showtime says Josh Hartnett and Eva Green have been cast in the period psychological thriller "Penny Dreadful."

Showtime's president, David Nevins, described the production as a scary monster story with a different look and style.

He told the Television Critics Association on Tuesday that It's the first genre series for the premium cable channel.

Hartnett will play an American who finds danger in Victorian London. Green, who starred in the James Bond film "Casino Royale," plays a woman who carries secrets and risk.

The eight-episode series was created by John Logan, whose credits include "Gladiator." He and filmmaker Sam Mendes are among its executive producers.

"Penny Dreadful" begins filming this fall for a scheduled 2014 debut on Showtime.