Zodiac

Drawn-out and detailed examination (with strong performances) of the still-unsolved Bay Area serial killings from the 1970s. The self-named Zodiac sends cryptic messages to the San Francisco Chronicle, where dissolute reporter Paul Avery (Downey Jr.) is on the crime beat. The paper's editorial cartoonist, Robert Graysmith (Gyllenhaal), figures out the killer's cipher and becomes obsessed with helping out. Then, SFPD detectives Dave Toschi (Ruffalo) and William Armstrong (Edwards) are assigned to the case, which eventually goes cold. Graysmith later wrote about the killings and drew his own conclusions as to the Zodiac's identity.