He is first seen when he is in a car talking to you about Gus and then after that he comes back and tries to steal the baseball card. You have to chase him and his true identity is revealed after Little Eddie knocks him out.
Gus starts suspecting him when you go into the back room of Good Deals Electronics and see the form for the new store for Preston Wilhelm, even though he already owns PrintFax. Notice that the New Store is right underneath Slugger's-Preston intended to drill a hole upwards into the safe to get the baseball card.
Preston's true identity as the thief.
Glitch where Preston Wilhelm decides to shove the wall instead of try to run away from you. Unfortunately, you can't catch him like this. :(
His last name is most likely taken from the Wilhelm scream, a famous stock sound effect for television and film.
Carnival Costumes | Coming Soon | Crawl Mart | Giuseppe's Toys | Good Deals Electronics | In The Now | Jolly Gifts | MacGuffin's | Main Street | Mall Atrium | Mall Left | Mall Right | Manager's Office | No Pain No Gain | Parking Lot | PrintFax | Security Office | Sizzle Tanning Salon | Slugger's Althetics Keepsakes