Martin pours himself a cup of tea and is about to break open a sugar packet to dump into his tea when Morwenna summons him of a patient who has arrived in his office, causing him to stick the unopened sugar packet in his coat pocket, a hint of something to come later on.
Martin's patient is an elderly woman (85 to be exact) by the name of Virginia who owns a chicken farm out by Joan's old house. Her worn face comes into his office, where she simply stares at Martin for a moment. Martin asks her to explain her problem to him. She responds, "I've got busted intestines!" Martin responds "You do not". Virginia: "Don't you tell me what I've got and what I ain't got! I've had one of them things run up me in the hospital and them doctor's told me my intestines, they's busted! I've got busted intestines!" Martin: "If your intestines had burst, you'd be dead". Virginia: "Well then I've made it alive through my busted intestines!". Martin proceeds to examine her and runs some tests and states he will have some tests results for her later, but she does NOT have "busted (er, burst) intestines". She responds "I do too."
Meanwhile, Nathan is managing to "tick off" the entire Portwenn School at his new position of school head master. He could care less what teachers or students he insults, and he finds his new position at Portwenn School extremely frustrating. Their technology systems, school plans and curriculum platform, and even bathrooms are "behind the times" for a cutting edge, educated PhD like Nathan, and he is seen griping over every little thing that happens to go wrong, frequently eyeballing a troublesome piece of technology, or even the bathroom faucet (when he lathers his hands up with soap and no water comes out!), and uttering which could become his second most widely used catchphrase in Portwenn, "be difficult". Nathan also happens to be an excessive clean freak and excessive organizer, frequently washing his hands and excessively organizing his office, as well as the school in general. Louisa visits the school to see how Nathan is getting on as the new head master, and he manages to get into an argument with Louisa, prompting her to utter the phrase "If I didn't know any better, I would say you're Doc Martin's brother!". Nathan infuriatingly tells Louisa to get out of his office.
As Louisa leaves the school, she sees Nathan get into a confrontation with a dog who tries to "enter" the Portwenn school, watching Nathan kick the dog and yell "get out, go away, you stupid animal". Ruth happens to catch a glimpse of Nathan's actions as well, heightening her suspicions about who Nathan could be.
Meanwhile, a new Portwenn resident from the states by the name of Janie Donovan with a heavy Southern US accent (she is from Texas, that will be so important to know later) comes speeding into Portwenn. PC Penhale watches a car come flying into Portwenn, and he goes after the "offender" in his police vehicle with lights flashing, the siren going, the works. Once he pulls over the "offender", "tough" PC Penhale gets out of his vehicle and demands the "speeder" to "exit the vehicle immediately". Out pops Janie, dressed to kill in a "sexy" outfit. Her "southern charm" is "love at first sight" for PC Penhale, and he totally melts in front of her after she gets out of her car. PC Penhale stutters and fumbles through the entire conversation. Janie does most of the talking for both her and PC Penhale, appealing to PC Penhale by pretending to be ignorant of the fact she was "speeding" or "doing anything wrong", explaining that in the states, she drives down "them big highways in Texas fast" and that she is "not used to these tiny little Portwenn roads". She convinces PC Penhale to issue her a warning instead of a speeding ticket, in which she gets back into her car and flies off, leaving PC Penhale still standing there, too stunned to barely breathe.
Nathan also revisits Large Restaurant, asking for what will become his signature dish request, a "chicken sandwich". Bert and Al simply glance at each other with a blank stare. Nathan goes on to explain it is a "fried or grilled chicken filet on a whole wheat bun". Bert and Al manage to whip together a "chicken sandwich" with some "Cajun seasoning", and surprisingly, Nathan seems pleased by their creation, although his praises come in very short, blunt remarks (of course!). It seems Portwenn's "chicken sandwich" is Large Restaurant's newest menu item, but their menu is about to get even "larger" (no pun intended) coming up.
Virginia's test results come in, and Virginia returns to see Martin. When she enters his office, she asks Martin "So how's my busted intestines?". Martin responds: "You do not have burst intestines". Virginia argues with him for a moment, then Martin shows Virginia her tests results indicating she has a mild issue that can be cleared up with a round of antibiotics. Virginia then responds "So I ain't got busted intestines after all?" Martin responds with "No". Martin is writing up Virginia's prescription and upon finishing, he is interrupted with an emergency call at the school…"Dr. Parker has passed out".
Backing up a bit, at the school, while teaching, Nathan begins to become dizzy and stutter and not be able to think clearly. He then "passes out", causing Martin to rush to the school in order to assist with Nathan's medical needs. Martin feels of Nathan and mentions to bystanders that he is clammy and sweaty and that he is suffering from a low blood sugar attack (his blood sugar has bottomed out). He dumps the sugar packet from his coat pocket into Nathan's mouth, causing him to quickly regain consciousness. Doc Martin brings Nathan back to his office, questioning him about his medical history and if there is any history of hypoglycemia in his family. Nathan responds that he does not know because he "never really had much of a family". He did not know his father very well (and it shows with his bitter attitude toward him) because his father was embarrassed with him for his arrival stemming from out of wedlock. He never knew his father's family, only that his father was a London surgeon. His mother primarily raised him on her own in Manchester, and he got his PhD at Wales before returning to Manchester to teach at the university. He fulfilled his "family void" by "burying his life in his studies" so he could be one of the finest lecturers and later on full faculty professors at Manchester before his medical condition struck him, causing him to have to relocate to Portwenn to become the new school head master.
Martin proceeds to take an A1C test with Nathan. Nathan becomes queasy then passes out while Martin is drawing his blood. Martin asks if his sugar bottomed out again once Nathan regains consciousness. Nathan responds by stating it did not. He has a "little problem…with blood", which begins to raise a red flag with Martin. Meanwhile, Ruth is at home searching through some of Joan's old photo albums, when she encounters some photographs of a young child who has a striking resemblance to, none other than, Nathan.