Frank Fisher, a former musician who has lost his wife in an accident, owns a vinyl store called Red Hook Records in Brooklyn, New York, who has not had any clients like in his day. His daughter, Sam, is about to leave West Coast to study medicine at the end of the summer. Despite Sam’s desire to study and spend time with her boyfriend, Rose, Frank insists very much on her singing together.
During a recording, Sam confesses that he composed a song he called “Hearts Beat Loud”. The two spend the whole night mixing and recording the whole song. Frank then uploads that song to Spotify without asking for Sam’s persecution, and the song immediately becomes viral, being highly appreciated by the listeners. Frank tries to convince Sam to set up a band in two, but the girl is hesitant, being determined to become a doctor.
However, Frank adopts a band title from Sam’s constant refusals and calls his collaboration as “We are not a band” (we are not a band). Sam secretly composed another song inspired by her relationship with Rose, and Frank in turn composes a piece inspired by the fact that he will have to close his business soon. Meanwhile, Frank’s most loyal customer, Leslie, proposes a way to save Red Hook by turning it into a café that would have the potential to attract more customers, but Frank stubbornly opposes it.