Seventeen-year-old Maddie O'Neill Levine was looking forward to spending her summer before college with her best friends. But everything changes when her grandmother, who also happens to be her closest confidante, announces that she is terminally ill and has booked a "death with dignity" cruise to spend her finals days with her family. Maddie finds herself on an eight-week cruise with her loveable yet dysfunctional family, learning about loss and unexpectedly falling in love.