Chad Fergus is the manager of the Fields Market in Frederick. He says the murder victim Barb Berquist was his best customer. Then Chad must help his cashier Crystal Booth and leaves alone. Later violet ink was found in the bones of the victim, and Brennan knows that Chad is the murderer of Barb. Booth and Brennan go back to the Fields Market to visit Chad. Brennan recalls that Chad has used a purple pen swabbed around the coupons. Booth and Brennan confront it and Chad Brennan finds the murder weapon at Chad's clipboard. Fergus finally confesses that he has Barb attacked because he had enough of their coupons, because he wanted his shop to have a good reputation.