As one of the most popular young-adult writers of the 21st century, internationally best-selling author John Green has become an entry point to the genre for many readers. His most-beloved book takes inspiration for its title from a famous line in Shakespeare’s Julius Caesar: “The fault, dear Brutus, is not in our stars, but in ourselves.” The Fault in Our Stars charts the love story of Hazel Grace Lancaster, a 16-year-old with stage IV thyroid cancer, and Augustus Waters, a 17-year-old in remission from osteosarcoma, a type of bone cancer that caused him to lose a leg, after they meet in a cancer support group. The 2012 release of the highly anticipated teen drama, Green’s fifth, made it an instant No. 1 best seller, and the book went on to spend 78 consecutive weeks on the New York Times best-seller list and sell more than 23 million copies worldwide. The cultural fanfare surrounding Green’s electric story continued when a movie adaptation starring Shailene Woodley and Ansel Elgort hit theaters in 2014. While so-called “sick lit” has in recent years faced criticism for romanticizing terminal illness and death, The Fault in Our Stars is an undeniable juggernaut of YA literature, offering a heart-wrenching portrait of the intensity of young love. —Megan McCluskey