'Mistresses' star Shelley Conn has been cast in the lead female role opposite Irish actor Jason O'Mara in the new blockbuster sci-fi series 'Terra Nova'.

Executive produced by Steven Spielberg, 'Terra Nova' follows the adventures of Jim Shannon (O'Mara) and his family who travel back to prehistoric earth as part of an experiment to save the human race.

Deadline.com reports that Conn will play Shannon's wife, Elizabeth.

Production on the series is due to start this month in Australia.

The series will begin on American television in the autumn of 2011, with a preview next May.