Max and Caroline select a factory to produce their cupcake T-shirts, but become suspicious of the work conditions at the factory after meeting the overly enthusiastic employees.
Caroline is shocked when she receives a Lamborghini for her birthday, which her father ordered for her four years ago. Meanwhile, Oleg has something big planned for Sophie.
Sophie's wedding shower is interrupted by a hostage situation. Max and Caroline's cupcake business gets unwanted attention when a tenant is arrested while wearing their company's T-shirt.
When Sophie takes Max and Caroline shopping for their bridesmaids' dresses, the girls enlist the diner gang's help to hide the ugliest ones, in the hopes of avoiding complete and utter humiliation.
Max and Caroline try to get Nash into the modeling business in an effort to bring in extra money acting as his managers. Also, Sophie and Oleg attempt to keep celibate for 30 days before their wedding.
Max and Caroline's attempt to break Nash into the modeling business comes to a screeching halt when his mother arrives from Ireland to retrieve her son.
Max and Caroline help launch the new branch of The High at JFK airport, and Sophie discovers that Oleg may have an ulterior motive for wanting to marry her.
In the fourth season finale, Max and Caroline are tasked with retrieving Sophie's wedding dress from customs and safely transporting it to the church in time for her big wedding.
Max, Caroline, and the diner crew rally together, when the city seeks to demolish the diner and cupcake window to build an I-MAX theater. Meanwhile, believing she is an expectant mother, Sophie takes many pregnancy tests.
Max and Caroline get part-time jobs at the juice bar at a gym to enjoy free use of the gym's locker room after their shower breaks; Caroline has a run-in with a group of rich moms who are jealous of the attention she's getting from a sexy trainer.
When the girls run into Caroline's newly engaged ex, Andy, Caroline wonders if she made a mistake when she sees how much he supports his fiancé's career.
Han insists the diner gang attends a mandatory night out in an "Escape Room Club" when he feels they aren't working together as a team, they soon find themselves locked inside the "Alice in Wonderland"-themed room.