Dan and Laura are a young couple going on vacation to a cottage. On the way, they stop off at a diner called The Sinner's Diner. A waitress named Denice seats them to a table and tells them to pick from their menu of sins. Each sin is coupled with a food entree. Murder comes with steak and vegetables, Sloth is a 12 inch hoagie, infidelity comes with salmon and potatoes...etc. Dan picks Envy and Laura picks Glutton as their meal choice.
So why does Denice keep bringing Dan the Infidelity meal (salmon, potatoes, and coleslaw) when he has clearly ordered something else. Denice insists that he ordered infidelity and that starts to drive him to the defensive. Getting angry, Dan starts to argue with the waitress. She insists that the Infidelity meal is exactly what he ordered.
More strange things happen in the restroom as Dan finds the name Tammy written on the stall. There's also a salmon meal floating in the toilet.
He sits back down and notices that Denice continues to serve him the Infidelity meal. Laura wonders why she hasn't been served her food yet. Denice reveals that she knows both of their names. Finally, Dan snaps and throws the food off the table. The food ends up back on the table.
Denice starts choking. She tried a bite of Dan's food and starts spewing a black liquid. Denice says that Dan's food is not for her. He checks on Laura who regains her health when she spits out the food. He then accidentally calls her Tammy.
Dan follows Denice into the kitchen where he finds that it has been abandoned for years. The kitchen is full of plates of salmon and potatoes. Every cupboard has the hated meal and it bogs down on Dan that he has a secret. Laura confronts him about who Tammy is. Surprise, surprise. Tammy is Dan's real wife and Laura is his side hustle. Dan explains that he needs to be a good husband and father, but his true heart is for Laura who makes him feel good. Laura explains how she met Dan: he consoled her after she went to her boyfriend's funeral. Dan was great guy, but she had no idea he had a wife and kids. She runs back to her table crying.
Dan begs Laura to calm down and accept that he can be married and have a woman he truly loves on the side. Laura is then served her meal. She mentions earlier that they serve a meal called murder (steak and vegetables). She ends the script saying, "I should tell you how my last boyfriend died."