Hazel, a 16-year-old girl, faces terminal thyroid cancer that has spread to her lungs. Despite this grim outlook, an anti-cancer drug called Phalanxifor has managed to shrink her tumors and given her a temporary reprieve. Even with this small victory, Hazel battles with depression and the harsh reality of her impending death. Her mother encourages her to attend a cancer support group, and Hazel reluctantly agrees.

At the support group, Hazel meets Augustus, a 17-year-old boy who has lost his leg to osteosarcoma. They instantly connect over their shared dark humor and their battles with cancer. Augustus is immediately captivated by Hazel's wit and beauty. After the session, Augustus invites Hazel to his house to watch a movie.

At Augustus's home, Hazel is touched by the warmth of his parents and the quirky collection of inspirational quotes plastered around the house. In the basement, Augustus candidly shares how cancer has altered his view on life. Their connection deepens as they watch the movie together, though both are nervous about showing affection.

During their time together, Augustus interestingly compares Hazel to Natalie Portman’s character in the film. Before Augustus takes Hazel home, they agree to read one another’s favorite novels. Augustus gives Hazel The Price of Dawn, and Hazel recommends An Imperial Affliction.