James Herriot arrives in the Yorkshire town of Darrowby to be interviewed for a job as a vet. With work hard to come by in 1936, James arrives only to find that his prospective employer seems to have completely forgotten about the appointment.

Siegfried's younger brother, Tristan, returns to Darrowby after failing his vet exams. James pays a visit to Mrs. Pumphrey to assess the health of her beloved dog, Tricki Woo, and also checks on Mr. Dean's dog too.

Siegfried employs Miss Harbottle to be a secretary for the surgery, but things do not go as planned when their ordinary routine is shattered. Meanwhile, James meets Helen Alderson and treats a calf for a broken leg.

Siegfried wins a major victory, Tristan is put on pig duty after a spell of drunkenness leads Siegfried to worry he is becoming lazy, and James discovers he has a rival in his pursuit of Helen Alderson.

Tristan offers James advice for his date with Helen, but their evening at a fine hotel does not go well. Later, Tristan arranges a double date for him with two local girls, but things once again take a turn for the worse.

Helen brings her dog to the surgery and James musters up the courage to ask her on another date. However, their romantic trip to the cinema begins to go wrong when the film is swapped at the last minute.

James offers his condolences to Mrs. Dalby whose husband recently died. He's a bit doubtful when she tells him that she'll be running the farm on her own. Things go from bad to worse when some newly acquired cows fall ill. Helen stops by the surgery and invites James to tea on Sunday. James gladly accepts and things are going well until one of Mr. Alderson's cows falls ill and James is unable to save it. Helen and James manage to overcome their bad luck however.

James discovers the source of the disease which is decimating the Dalby family's cattle, and he also makes some big decisions regarding his future with Helen. Meanwhile, Tristan and Siegfried are overwhelmed by the size of Mr. Mulligan's dog.

James and Helen are due to go on their honeymoon, and Tristan gives James advice on his honeymoon plans and suggests a Mediterranean cruise. James couldn't possibly afford it and Tristan suggests he try his hand betting at the track. Siegfried is invited to the Broughton races and he knows the racing circuit is looking for a new vet. Plans for the honeymoon are threatened when the Ministry of Agriculture announces imminent tuberculosis tests at the surgery.

James and Helen are on their honeymoon and start the tuberculin testing. They're staying at a local inn but are constantly interrupted by the landlady. Back at the practice, Siegfried hires a new student vet and James, on a working honeymoon with Helen, takes him out on his rounds. However, it quickly becomes apparent that the new vet seems to know virtually everything already.

James works with young, hard-working farmer Frank Metcalfe, who has relocated from the city. Unfortunately his herd is diagnosed with brucellosis, which has both immediate and long-term effects. Tristan returns from school and meets Richard Carmody. The vets and the village doctor see an opportunity to teach Gobber Newhouse, a local bully and wife-beater, a lesson when he steps on a rusty nail and needs care.

Tristan has failed his final exams and must now tell Siegfried. He decides to soften up Siegfried a bit, starting an exercise program and cutting out drinking and smoking. James has to deal with Mrs. Donovan, a self-styled animal healer whose dog is killed in an accident. When he's called in by the local constable to deal with a case of animal cruelty, he knows just who to call on to find it a home. Finally, James must assist cranky Angus Grier, a neighboring vet who has a broken arm.

When foot-and-mouth disease strikes, Siegfried confines himself to Skeldale House. Meanwhile, James administers a large dose of anaesthetic to an animal and expects it to pass away, but it surprises him by making a full recovery.