Only Fincher could get away with not only making a murder mystery movie that doesn't fully reveal the killer(mainly because it's based off a true story), and have it be possibly the greatest detective mystery film of all time. Casting was on fucking point creating a fantastic ensemble, the dialogue felt incredibly real(also funny at times), and some scenes like when Graysmith is about to go into the basement or when Zodiac stabs his victims in the back are just so goddamn terrifying.