Prime Number Case

While the Inspector and FBI agent Ted are in their hideout fishing store fishing store, three men hold it up. Value taken is under $1000. They steal everything in the glass counters, at the front of the store. Several hours later a similar layout is robbed of $250,000 of jewelry in Portland. The Seattle store was practice?
The three men are found dead in a large walk-in safe for no reason. Was the real target the fishing store and what is under the glass? How can a UW mathematician help solve either case with prime numbers?
How many other safes are in danger from being open with no alarms being given?
Is trying to tail a suspect in a town of one-way streets easy when he j-walks and changes direction in a second?