When she discovers a love letter written to her husband by an unknown paramour, the distraught Eliza turns to her tight-knit Long Island family for advice. Soon the entire clan, strong-willed mom, taciturn dad, and jaded sister with pretentious boyfriend in tow, has squeezed into a station wagon and headed into Manhattan to find out the truth, kicking off a one-crazy-day odyssey full of unexpected detours and life-changing revelations.