Ep 11. Coupon Coup

In Mystery Diners season 5 episode 11, titled "Coupon Coup," host Charles Stiles and his team of undercover diners are called in to investigate a family-owned Italian restaurant in Chicago. The restaurant owner, Maria, is concerned about a sudden decrease in profits and suspects that someone on her staff might be stealing from her.

To get to the bottom of things, Stiles sends in one of his undercover diners posing as a regular customer. The diner, named Kyle, is armed with a coupon that offers a substantial discount on his meal. As Kyle dines in the restaurant, the Mystery Diners team observes from a hidden control room, using hidden cameras and microphones to gather information.

It doesn't take long for Kyle to notice some suspicious behavior from one of Maria's employees, a waiter named Vinnie. Vinnie seems overly concerned about Kyle's coupon and tries to convince him to choose certain menu items that aren't covered by the discount. He also seems to be trying to rush Kyle out of the restaurant as soon as possible.

As the investigation continues, the Mystery Diners team uncovers more evidence of wrongdoing by Vinnie and some of his co-workers. They discover that Vinnie has been pocketing extra money from customers' bills by adding additional charges for items that they never ordered. Other employees have been helping him by not reporting the discrepancies to Maria.

Stiles decides to confront Maria with the evidence and she is shocked to learn what has been going on in her restaurant. The Mystery Diners team sets up a sting operation to catch Vinnie in the act of theft. They invite a group of diners to the restaurant and give them coupons with a hidden camera inside. When Vinnie tries to overcharge the group, he is caught on camera and immediately fired by Maria.

In the end, the Mystery Diners team helps Maria implement new policies and procedures to prevent future theft and ensure the continued success of her restaurant.