Jack and Terry. Hank and Edith. They're married couples and best friends with much in common. Jack and Hank are professors at Cedar County College. Terry and Edith are stay-at-home moms. And Jack and Edith are secret lovers. Mark Ruffalo, Laura Dern, Peter Krause and Naomi Watts play the interlocked foursome, pushing their characters into uncharted realms of anger, confrontation and lust - and making decisions that might or might not let love slip away.