Many people approached George R.R. Martin to produce a movie for his unfinished "A Song of Ice and Fire" series, but he refused them all, thinking that it would be too expensive to produce accurately. When the showrunners Benioff and D.B. Weiss told him that they wanted to make a series out of it, Martin asked them one question that sealed the show's fate. The mastermind behind the books' many twists and turns wanted to know who they thought Jon Snow's mother was. Benioff and D.B. Weiss's answer satisfied the author and he sold the rights to the book.