Hazel Grace Lancaster is a teenager, living in the suburbs of Indianapolis, who has thyroid cancer that has spread to her lungs. Believing she is depressed, her mother Frannie urges her to attend a weekly cancer patient support group. There Hazel meets Augustus "Gus" Waters, who lost a leg to bone cancer but has since apparently been in remission. The two bond over their hobbies and agree to read each other's favorite books. Gus gives Hazel Counter Insurgence, while Hazel recommends An Imperial Affliction, a novel about a cancer-stricken girl named Anna that parallels her own experience, but has an abrupt ending. Its author, Peter Van Houten, retreated to Amsterdam following the novel's publication and has not been heard from since.
Weeks later, Gus tells Hazel he has tracked down Van Houten's assistant, Lidewij, and has corresponded with Van Houten via email. Van Houten explains that he is only willing to answer their questions in person. Gus then surprises Hazel with tickets to Amsterdam, acquired from the Make-A-Wish Foundation. After a medical setback, Hazel's doctors eventually allow the trip.
Hazel and Gus arrive in Amsterdam and Gus confesses his love for Hazel during a romantic meal sponsored by Van Houten. The following afternoon, they go to Van Houten's house, but are shocked to find out he is a mean-spirited alcoholic. It is revealed that the emails from Van Houten had actually come from Lidewij, who arranged the meeting without Van Houten's knowledge. Van Houten taunts Hazel for seeking serious answers to a piece of fiction and belittles her medical condition. The teens leave, utterly distraught. Lidewij invites them to go sightseeing to make up for their ruined experience and they visit the Anne Frank House, where they share their first kiss. The next day, Gus tells Hazel that his cancer has returned, spread throughout his body, and is now terminal. Hazel is heartbroken, but hopeful.
After their return to Indianapolis, Gus' health only continues to deteriorate. Gus invites Hazel and his best friend Isaac to his pre-funeral, where they deliver eulogies that they have both prepared. Hazel tells him she would not trade their short time together for anything. Gus dies eight days later. Van Houten attends his funeral, revealing that Gus had demanded he do so. Van Houten explains to Hazel that An Imperial Affliction is based on his own daughter, Anna, who died from leukemia at a young age. He gives Hazel a piece of paper, which she initially discards, but later retrieves after a conversation with Isaac reveals that the paper was a letter from Gus, not Van Houten - the former had asked Van Houten for his help in writing a eulogy for Hazel.
Hazel reads the letter, in which Gus accepts his fate and professes his love for Hazel. It concludes with, "Okay, Hazel Grace?" As Hazel finishes the letter, she lies on her back in her lawn and looks up at the stars, responding, "Okay."
Shailene Woodley as Hazel Grace Lancaster
Lily Kenna as young Hazel[8]
Ansel Elgort as Augustus "Gus" Waters[9]
Nat Wolff as Isaac, Augustus' best friend[10]
Laura Dern as Frannie Lancaster, Hazel's mother[10]
Sam Trammell as Michael Lancaster, Hazel's father[11]
Willem Dafoe as Peter Van Houten[12]
Lotte Verbeek as Lidewij Vliegenthart, Van Houten's assistant
Mike Birbiglia as Patrick, the support group leader[13]
Ana Dela Cruz as Dr. Maria
Milica Govich as Mrs. Waters, Augustus's mother
David Whalen as Mr. Waters, Augustus's father
Emily Peachey as Monica
Emily Bach as Monica's Mom
Carole Weyers as the voice of Anne Frank
based on the 2012 novel of the same name by John Green.