The film opens with a 20-30 minute prologue establishing Jill and Isabelle's close bond while growing up in Austin as Isabelle manages cystic fibrosis. Years later, Isabelle passes away. In her grief, Jill moves to San Francisco, works under Chef Bastien, and leaves voicemails on Isabelle’s old number.
The line is reassigned to Wes in Austin. Entranced by her voicemails, Wes travels to SF and plans an encounter near the Golden Gate Bridge. They begin dating, but during a cozy evening, Jill wears Wes’s jacket, hears his secondary work phone ring, and realizes he is the person receiving her private messages to her sister.
Heartbroken by the betrayal, Jill breaks up with Wes and returns home to Texas. On New Year’s Eve, Wes re-purchases Isabelle’s old phone line, transfers it back to Jill’s account so she can keep her audio connection to her sister, and leaves a final message inviting her to José's Tacos. They reconcile at the restaurant, recognizing that while their beginning was imperfect, their love is genuine.