20 Things You Didn't Know About Zodiac
15. The Colour Blue Is Dominant Throughout (For One Particular Reason)
Though Fincher's films more often than not favour dank, jaundiced yellows, Zodiac has a particular penchant for chilly blue in an attempt to reflect one of the movie's key plot points.
At one point Robert Graysmith (Jake Gyllenhaal) notes that Zodiac tends to pick victims close to bodies of water, and to mirror that, blue is prominently featured in numerous scenes.
The Zodiac's letters are written in blue ink, Graysmith wears a blue piece of clothing in almost every scene (while other characters regularly wear blue), he and Avery drink bright blue cocktails called Aqua Velva (which features Blue Curaçao as a main ingredient), the song playing in the bar is "Crystal Blue Persuasion" by Tommy James and The Shondells, and Graysmith's home phone is even light blue.