It's worth remembering that one of the most esteemed films of all time stemmed from a pretty pulpy, if undeniably page-turning, source novel. Francis Ford Coppola actually didn't really want to adapt Mario Puzo's The Godfather initially, agreeing to it mainly because American Zoetrope had fallen on hard times. Written by Coppola and Puzo along with Robert Towne as an uncredited script doctor, the film is widely considered superior to the book thanks to the removal of unnecessary subplots and a cleaner focus on characters and examining the corruption of power.