During Riddick's detainment in the station he was evaluated by Dr. Snyder. who attempted to analyze Riddick; he did not make much progress. Dr. Snyder attempted to work with Riddick. The doctor asked Riddick to draw his earliest memory. Instead Riddick drew a detailed schematic of the entire prison cell-block, with an escape route.
Later, Riddick drew what appeared to be four indeterminate blobs. Dr. Snyder assumed that Riddick was mocking him. When Riddick attempted to escape he killed four people, whose corpses appeared laying in essentially the same shapes that Riddick had drawn.