The series is based on the best-selling novel of the same name by Caroline Keness. "What would you do for love?" After a talented bookstore owner meets an aspiring female writer, he finds the answer to this question: anything. He collects all the private information about her through the Internet and social media, tries to get close to her, and quickly turns from self-absorbed and awkward love at first sight to morbid obsession, quietly and skillfully removing all obstacles in the way of love, even living people. The series stars Penn Badgley, Elizabeth Lail, Shay Mitchell, Luca Padovan and Zach Cherry.