Breakthrough Hit: John Green has had many popular books before this, but this was his first massive hit and the book that really brought him into public eye. In 2014 alone, only the Divergent trilogy has been able to rival it in sales.
Shrug of God: John Green has had to do a lot of this to fans who want to know what happened to the characters before/after the contents of the book; this becomes somewhat humorous in light of the fact that there’s also a significant in-universe example where Hazel and Augustus ask Van Houten what happened to the characters of An Imperial Affliction and he tells them he doesn’t know.
Star-Making Role: For Ansel Elgort. Divergent also got him attention, but this is the film that shot him to the stratosphere.
What Could Have Been: Green's original ending had Hazel and Van Houten try to find a way to honor Gus's death by dying themselves in a way that would accomplish something and was meaningful to his life. They decide to go out and kill a drug lord, then die at the hands of his bodyguards. One editor, upon reading this ending, remarked, "I can't tell if the last 40 pages are a joke." The again, neither can John Green himself.
Originally, the story was going to be from Isaac's point of view.