Plot
Andy Jones is head chef of Jones & Sons, an upmarket restaurant in London. Andy is embarrassed to learn that his restaurant has been downgraded from a Food Hygiene Rating of 5 to a 3 following an audit by a food inspector, mostly due to insufficient administration and subpar sanitation at several work stations: new cold chef Camille washed her hands in the food preparation sink; while demi-chef Tony was not wearing gloves shucking oysters, thus risking cross-contamination.
After the inspector leaves, Andy reprimands the kitchen staff for their lack of thoroughness, albeit backtracks upon learning the turbot he prepared earlier was discarded by the inspector for being unlabelled. Front of house manager Beth calls a meeting to discuss the evening's service being overbooked and warns short-fused saucier Freeman about his loud swearing. She then mentions they have a marriage proposal at one table; and also, a booking for celebrity chef Alastair Skye (with whom Andy previously worked) plus his guest, Sara Southworth—a known food critic. Andy is frustrated that Beth didn't forewarn him in time to prepare.
During dinner service, conflict begins to brew in the kitchen and dining room. Beth annoys the kitchen staff with micromanagement; the intended proposal girlfriend Mary's nut allergy was not entered into the system beforehand, irritating sous-chef Carly; Andrea, a black waitress, is treated with hostility by an aggressive racist guest, in contrast to her white colleague, Robyn; young pastry chef Jamie is revealed to be self-harming, but is comforted by mentor Emily; Sophia, a pregnant kitchen porter, spars with lazy, disrespectful co-worker Jake; the French Camille struggles with Andy's scouse and other British regional accents; and Tony feels out of his element at an atypical station.
Tension is further exacerbated when Beth demands the already-stressed chef Carly go off-menu by preparing steak and chips to appease a group of "influencer" guests. When a lamb dish is returned for being supposedly undercooked, Carly berates Beth. She blames Beth for neither properly instructing her staff nor entering guests' food allergies into the system beforehand. She scolds her for failing the restaurant with her insufficiency, and that no staff member likes her. Carly is also outraged to learn indirectly that she will not be getting a wage increase. Beth retreats to the toilets in tears, admitting to her father, the owner, on the phone that she feels inadequate.
Andy serves Alastair's table, where Alastair reveals that Andy owes him £200,000 and wants the payment in full to cover his private losses. Andy explains that he cannot reimburse him. Alastair offers to work together with Andy again and proposes that he should get a 70% share of the restaurant, leaving Andy and his other investors with just the remaining 30% to share between them. Meanwhile, the waiter Dean charms a group of ladies, one of whom inappropriately spanks him. Bartender Billy flirts with Robyn and they make plans to go to the club where Dean is DJing.
Mary suffers a severe allergic reaction, Camille is soon aware she has caused the error. Taking advantage of the situation, Alastair insists to Andy that Carly be the scapegoat, or else the restaurant—as well as their potential partnership—will fail. After Mary is picked up by an ambulance, the kitchen staff and Beth meet at the back of kitchen to determine the cause. They conclude that it was Andy's fault the food was contaminated: Earlier, he had unwittingly instructed Camille to use a bottle, containing walnut oil, as a substitute garnish. This culminates in Freeman chastising Beth, then lambasting Andy for his incessant tardiness, mistakes, and alcoholism. A fight nearly erupts between Andy and Freeman, which Carly prevents.
The staff return to work as Carly attempts to quell Andy, until he reveals that Alastair insisted he lay the blame on her. Carly subsequently reaches her breaking point and declares she will seek another job. Andy goes to his office, where he has a mental breakdown. He drinks vodka and snorts cocaine. It is also revealed that the water bottle Andy had been repeatedly drinking from throughout the film did, in fact, contain vodka. He calls his ex-wife and asks her to tell his son he loves him, and that he will go to rehab.
After ending the call, Andy disposes the drugs and liquor and goes back to the kitchen but on his way there, he collapses to the ground. The staff's voices are heard calling his name frantically.