Regrets take over Cooper's life. Literally. As a radio host, she spends her days reading anonymous letters about heartbreak and regret on her segment Regret Radio, immersing herself in other people's stories to avoid facing her own. But no matter how far she runs, her past is always there, reminding her of the mistakes she's made. One of those regrets? Losing her childhood best friend. And it doesn't help that he's no longer just a memory, he's global superstar Harry Styles. He's everywhere. And just when she thinks she can escape through Regret Radio, a letter arrives that drags her straight back into the past.