I was in secondary school when I first saw a copy of The God Father by Mario Puzo. The most remarkable memory I have about that book was the cover design (by S. Neil Fujita). That was my first memorable observation of how simple geometrical shapes and negative space can have powerful graphic impact. These elements have since been my working tools for poster or book cover design over the years.
Above is my take on a crime thriller poster design. The work was done on CorelDRAW.