British couple Liv and Will seem to have it all: A rock-solid marriage, a glamorous new life in New York thousands of miles from their provincial hometown, and still young enough to feel that their whole lives are ahead of them. Until Liv learns about Will's affair. Heartbreak is swiftly followed by another emotion - fury. Revenge is her only option, and when Will proposes a trip around America's epic National Parks to give their relationship a fresh start, she knows just the place...