Joshua Jackson has joined the cast of Showtime’s drama pilot “The Affair.”

He’ll play a hard-edged cowboy who manages a ranch on Long Island and is married to a woman who begins an affair with a Gothamite spending the summer on the island with his family. Dominic West, Ruth Wilson and Maura Tierney also star in the pilot, which will tell the story of the affair separately from male and female perspectives.

“Affair” is penned by Sarah Treem (“House of Cards”) and Hagai Levi (“In Treatment”). Treem and Levi exec produce along with helmer Mark Mylod.

“Dawson’s Creek” alum Jackson is coming off a five-season run on Fox’s “Fringe.” Recent film credits include “Lay the Favorite” and “Inescapable.”