22-year-old Tess moves to New York City for a blank slate, without friends or a specific ambition. After an intense interview at one of the city's best restaurants, she's invited to train to be a back-waiter. On her first day, she attempts to keep up with this fast-paced world of serving while observing the complicated dynamics among her new coworkers.

When Tess forgets her wallet at the restaurant, she goes back to discover what happens after-hours: shift drinks. At the end of shift, each employee is entitled to one drink - or ten. As Tess sips her wine, Simone teaches her about the coding of our tongues: sweet, salty, sour, bitter, leading Tess to become even more enthralled by Simone. Sasha then recruits Tess to find his missing "green card wife." Along the way, Tess finds out where everyone goes after they've clocked out for the night.

Tess is beginning to master some essential back waiter skills, but there is still one thing she struggles with: the three plate carry. She asks Will to help her practice after work, which leads to her first romantic encounter with a coworker. The next shift, Tess meets Serena, an alumna of the restaurant who married one of their wealthiest guests, Fred Benson. Serena and Simone were best friends until Serena chose to leave the restaurant and settle down. To Tess, Serena has the picture-perfect New York life. But Simone teaches Tess not to believe everything she sees.

Tess finally has a day off from the restaurant. Instead of running errands or doing laundry, she wants to explore her new city. She goes to an art museum, where she runs into a childhood friend and her mother. They startle her, and her life doesn't sound as impressive as it feels: Her day is definitely not going as planned. Tess decides to go to Simone's apartment unannounced to borrow her wine books. Simone's apartment is all Tess could hope for: filled with artifacts from traveling the world, various books Simone has read, and a perfect bathtub directly in the middle of the kitchen. After Simone invites Tess into her intimate world, her abrupt expulsion leaves Tess lonelier than ever. She goes back to the only place she knows: the restaurant.

Tess arrives at the restaurant in high spirits, but soon realizes this is a night where everything will go wrong. The dishwasher is broken, a hostess and bartender are missing, and Sasha is upset that Howard still will not promote him to server. After an exhausting and chaotic shift, Tess and Sasha embark on a drug-fueled night of dancing and adventure to burn off the stress of work. They follow Ari from her DJ set at a club to her surprisingly fancy apartment, all while reflecting on the many flaws of the restaurant. Tess keeps thinking things couldn't get any worse, until the night takes a dangerous turn.

After a long night of partying until sunrise, Tess finds herself in a less than ideal state for her big day at the restaurant. Today is her final exam, and she will either pass her trials and be hired as a backwaiter, or fail and lose her newfound family for good. Tess is initially desperate to do well on her last day of trials, but the day's events make her question if this job is really worth it. The blows keep coming as Tess learns more about her coworkers, injures herself, and makes a mistake that could endanger her chances of being hired at all. On the brink of joining the restaurant family as a backwaiter, Tess asks herself: do I really want this?