Zodiac
Based on the Zodiac killings that occurred in 1960 California, Zodiac follows a team of detectives who try to crack the - still cold - case. It tells the story as it happened and doesn't offer the viewer any clean or wrapped up ending. Directed by David Fincher, he spent 18 months researching for the film and wanted to purposely leave the end unresolved. That's probably why it wasn't a huge box office hit but was still hailed as some of Fincher's best work.