Season 5

The owner of Source in San Francisco has concerns about meat being served in his vegan restaurant. The Mystery Diners point to bigger problems with his male cashier eating outside food at the restaurant in addition to lying to customers about meat being served, another cashier named Sydney is being rude to customers with her vegan ways, and his head chef coming in to work intoxicated while drinking booze hidden in a drink cup. During the confrontation, the male cashier storms out, the chef is forced to take time off, and Sydney is reprimanded to ease up on customers. The narrator reveals that the former cashier has found employment elsewhere. The chef is attending Alcoholics Anonymous. Sydney has adopted a more friendly approach.

The owner of Looney's BBQ in San Leandro, California asks Charles to investigate his staff when he hears that some of them are pranking customers with the restaurant's Devil's XXX hot sauce. He is shown why by the Mystery Diners when his waiter Matt and manager had been behind the pranks. The manager is disciplined by the owner and asked to be more friendly to the staff while Matt is fired. In his exit interview, Matt stated that he didn't regret his actions in giving some of the customers the XXX hot sauce because they were acting bad around him and he believed they deserved it. The narrator revealed that Matt had found employment elsewhere. The manager has adopted a more friendly approach and no longer hazes the staff.

Charles Stiles investigates a rumor of a new manager who is running unauthorized promotions at Rocco's Cafe in San Francisco (which has a photo gallery of famous people on it's wall) upon being called in by Don Dial. Don had a right to be concerned with his manager running his own get rich quick scheme by having his friend pose as Jamie Foxx and giving customers a photo of Jamie Foxx and/or an autograph for a fee. Don was incensed and states to Charles that he would not give even the Mayor of San Francisco exclusive seating. In addition, it was also discovered that a busboy has been eating on the job and lying about not speaking English. During the confrontation, Don fired the busboy for his actions and lies. When the manager tries to justify his actions, he is also fired. The narrator revealed that the former manager have found new employment. In addition, the former busboy has since stopped lying about not speaking English. The waitress has been promoted to manager.

The owner of Chapeau! in San Francisco asks the Mystery Diners to investigate allegations that his waiting staff is rude to customers. The Mystery Diners confirm the owner's suspicion when his French-speaking waiter Renaud is rude to customers and is caught smoking outside to alleviate his stress while struggling to quit. Soon, they point to bigger problems with another waiter named Michael who is caught stealing Renaud's tips, taking them as his own and soliciting other customers for more tips. The owner's son is not doing his job and is seen kissing his girlfriend who is the hostess of Chapeau!. When all three are confronted, Renaud and the owner's son both apologize for their behavior and are reprimanded, while Michael is fired. The narrator revealed that Michael is now waiting tables at another restaurant. Renaud has quit smoking and has since adopted a friendlier approach. The owner's son has been doing a better job at work and is going steady in his relationship with the hostess.

Cindy, the co-owner of Speisekammer is Alameda, California believes the "Dirndl Girls" hired by her ex-husband, Peter, are the source of many problems. Peter disagrees and thinks it's her recently hired waiter named Tim that behind the problems. They Mystery Diners show Cindy why she had a right to be concerned when they point to big problems with two of the Dirndl Girls named Angela and Shana. They are not only speaking poorly of her behind her back, but are also drinking on the job, stealing tips, and rigging the mass holding competition to allow their friends to win. Only one Dirndl girl named Danielle, is actually a model employee. Bigger problems are exposed when Tim is revealed to be involved with Angela and Shana's scheme.

The owners of Bistro Baffi in Burien, Washington ask Charles Stiles for help when expensive bottles of wine go missing as well as priceless art pieces. The Mystery Diners are able to show the owner that the manager isn't paying attention to the theft and has been conducting secret art deals. His waitress had also been taking bribes from other customers to let them take the wine bottles home. During the confrontation, the waitress and the manager are fired by the owners. The narrator revealed that the former waitress has apologized for her actions and found employment elsewhere. The former manager still maintained that he did nothing wrong. The staff had now been better trained to watch the wine and art better.

Nader, the owner of My Greek and Italian Restaurant in Tacoma, Washington notices an increase in broken plates and customer complaints with his staff. The Mystery Diners show Nader that he had a right to be concerned when they point to big problems with his assistant manager named Steve who is the direct cause of the customer complaints. He had been showing up to work intoxicated by putting too much shots in a traditional Greek appetizer called a saganaki (only calling for one shot), breaking the rules in conducting the Greek tradition of breaking plates and also tricking one of the busboys named Travis to get involved in his own get rich quick scheme.

After inheriting some of their staff from the previous owner, the new owners of Sam's Tavern in Seattle believe there is a divide between the old employees and their new employees. The Mystery Diners point to the manager who had been misbehaving herself with the belief that the previous owner should've made her the new owner of Sam's Tavern and had been abusing the new waitresses. During the confrontation, the manager is fired from her position. The narrator revealed that the former manager has found employment elsewhere. The old employees have been treating both their new owners and their new employees with respect.

Blaine Cook, the owner of Zippy's Giant Burgers in Seattle, calls Charles Stiles to investigate rumors he's heard that his employee Aaron working as the costumed mascot Zippy the Yum Yum Burger Boy is misbehaving. The Mystery Diners go undercover and point to big problems when they reveal who was behind the whole misbehavior, Aaron's friend and roommate named Dopey Dan. He has been showing up intoxicated as a favor while Aaron visits his sick mother in secret to handle her errands. When the two are confronted, Blaine expresses his disappointment in Aaron for having Dan cover his shifts. Stiles asks Aaron why he doesn't have Dan take care of his mother's errands. Aaron stated that he wouldn't trust Dan to do any sort of errands for his mother. Stiles also points out that he made the mistake of trusting Dan to come to his place of work to cover his shifts and having him wear the Zippy costume while intoxicated.

The owner of Taverna Mazi in Seattle believes his staff are getting too carried away with ghost stories and "haunted tours." The Mystery Diners shows him why with his waiter and busboy pulling pranks. During the confrontation, the waiter and busboy are fired for their actions. The narrator revealed that the former waiter and busboy have found employment elsewhere. Unfortunately, Taverna Mazi has closed down due to increased paranormal activities.

The owner of The Hangout in California notices a large increase in the number of coupons used. The Mystery Diners point to the manager who isn't doing his job and leaves work to go surfing in the middle of his shift and one of the waitresses who is selling coupons to her co-workers from a blank roll of register tape. During the confrontation, the manager and waitress are both fired. The narrator revealed that the former manager has apologized for his actions and frequents the restaurant as a patron. The waitress has found employment elsewhere. All other problem employees have been terminated and replaced with new employees.

Charles helps the owners of Redballs Rock & Roll Pizza in Moorpark, California after finding discrepancies in their pizza supplies. The Mystery Diners point to bigger problems with their manager and one of the waitresses behind the discrepancies: the manager has instructed the waitress to ring up a slice of cheese pizza as beer to pay the bands with beer, in addition to using his own bouncer at a door to collect money from patrons at the door and inside the restaurant for himself, and withholding money payment to the bands. With one of the bands about to take their truck in response to being owed money, the male owner run out and stops them from driving off. He and his wife both confront the manager and waitress involved and fire them both.

The owner of the Encore Dinner Theater suspects a relationship between an actress and one of his waiter is affecting customer service. The Mystery Diners discover that one of the waiters is trying to romance an actress that doesn't return her affection to him. In addition, the bathroom attendant has been demanding tips from the customers. During the confrontation, the waiter is fired and the bathroom attendant storms out. The narrator revealed that the former waiter is working as a waiter at another restaurant. The former bathroom attendant was replaced with a less-pushy bathroom attendant.