For Cath and James, summer has always meant his garage-band chords, her family's dinners, and the certain, simple truth of 'us.' They are the couple everyone knows-childhood sweethearts with a future as wide-open as the road they plan to travel after graduation. But in their last summer before senior year, a different kind of test begins to rewrite a story they thought they knew by heart. Now, they must navigate the terrifying leap into adulthood while holding onto what made them 'Cath and James' in the first place. This is not a story about how they fell in love. It's the story of how their love learns to grow up.