Everything, Everything Summary

On the cusp of her eighteenth birthday, Maddy is confined to her residence in Los Angeles due to a Severe Combined Immunodeficiency (SCID) diagnosis. Her mother, a physician, and her full-time nurse, Carla, attend to her in her carefully sealed home. A tragic accident led to the death of her father and brother when she was an infant. Serendipitously, a new family arrives next door, and Maddy forms a bond with Olly, the boy from the family, via the internet and mimed chats through windows. Soon, the friendship evolves into a romantic relationship when Carla permits Olly to visit Maddy without her mother's knowledge.

Olly and Maddy's secret is exposed when Maddy impulsively intervenes in a domestic dispute between Olly and his father. Upon discovering the visits, Maddy's mother dismisses Carla, and Olly is compelled to resume school. Despite the upheaval, Maddy continues to communicate with Olly while attempting to mend her strained relationship with her mother. To truly experience life, Maddy decides to risk it all by planning a brief trip to Hawaii with Olly. Despite some initial reluctance, Olly accompanies Maddy, but their dream trip takes a bitter turn when Maddy falls ill and is hospitalized. A worried mother tracks Maddy to Hawaii and immediately brings her back home.

Back home, Maddy attempts to restore her prior life, cutting ties with Olly, and her mother, in an attempt to ease Maddy's sorrow, reemploys Carla. In a twist of fate, the doctor who treated Maddy in Hawaii expresses doubt about her SCID diagnosis and recommends she seek a second opinion. After an investigation into her mother's files, Maddy uncovers that she does not have SCID, and her mother's obsessive protection was born out of her grief over losing her husband and son. Angered and betrayed, Maddy plans to leave, but Carla advises her to empathize with her mother. During her flight to New York, Maddy begins to forgive her mother and is joyfully reunited with Olly upon arrival.