When you abandon the rules, can you ever go back?

Mia Allen has never quite adjusted to living in England. She misses her friends in the States and feels restrained by small-town family life near Oxford. Her husband Kit, on the other hand, loves the sense of community here and his job as a school teacher in a private school.

Like Mia, Kit's boss Charlie is also looking for more excitement in her life. Her marriage to emotionally-distant Rob has left her frustrated and yearning for more. So when she and Rob are invited to dinner with Mia and Kit, she jumps at the chance to make new friends.

One evening, the increasing attraction between all of them moves up a notch, and it's not long before the seductive highs of these new friendships lead to desperate lows. Can any of their relationships survive this unconventional arrangement?