Maggie Sherwoode is the longtime personal assistant to legendary R&B singer Grace Davis who still has a successful touring career despite not releasing new material for a decade. Maggie is also an aspiring music producer, remixing Grace’s songs in her free time. Grace’s manager, Jack Robertson, believes that her time has passed and she should accept a Las Vegas residency and continue releasing live albums rather than record new material.
At a grocery store, Maggie meets aspiring musician David Cliff and watches him perform outdoors. He invites her to a party at his place, where to her surprise she learns that despite slumming it as a musician he is quite wealthy. Impressed by his voice, she lies about being a professional producer and offers to work with him on an album. He accepts and the two begin work together with Maggie coaching him through his nerves.
Grace is displeased when a popular music producer remixes one of her songs to modernize it with excessive synths and pop elements. Appalled, Maggie shows Grace her own version of the song, and Grace decides to release Maggie’s version, without payment or credit. While Maggie is pleased to be producing for Grace, Jack pulls her aside to reveal how her tactlessness ruined potential future deals. Grace later expresses her interest in recording a new album to her record label. They discourage the idea and push her towards the Vegas residency to Grace’s embarrassment. Maggie encourages Grace to disregard the label and create new material but Grace lectures her on how women of her age and race rarely succeed in music.
Maggie and David begin a romance as recording for his demo comes to a close. At the same time, Maggie learns that Ariana Grande has backed out of opening for Grace’s album launch. She initially books Dan Deakins to open for Grace before realizing the album launch would be the perfect place for David to perform his songs. She enlists Dan’s assistant to help but is surprised when Dan himself, after listening to David’s songs, decides to step away to allow him to perform.
The night of the party, Maggie tells Jack and Grace that Dan has backed out and promises to fix it. She then asks David, who believed they were going on a date, to sing. After hearing that the party is for Grace Davis, David leaves in a huff, refusing to perform. Maggie tells Jack and Grace she was unable to deliver a backup performer and Grace berates her, mocking her ambitions to become a producer when she cannot even succeed as an assistant before firing her.
Maggie moves back home with her dad Max, a radio DJ, and starts planning her future. After encouragement from her father, Maggie reaches out to David to continue work on their album and to Grace to thank her for her time working for her. At the same time, Grace realizes that she misses Maggie who was a faithful assistant who never used her.
Grace arrives at Maggie’s home and reluctantly offers a roundabout apology. After complimenting her production work on the live album, she reveals that she has never worked with a female producer before but wants Maggie to be the first, also telling her that she has begun writing new material. As she is singing for Maggie, David arrives. Before Maggie can introduce them to one another, David reveals that Grace is his estranged mother, something she has kept from the public. David also tells Maggie that Dan Deakins has been passing around his material leading him to receive an offer of representation from a studio.
Later on, David performs at a music festival. He asks Grace to join him on stage, revealing she is his mother, and the two sing a duet as Maggie watches. Later in the studio, Maggie produces Grace’s new album.