Having failed his exams, Tristan fears his brother's wrath. In a desperate effort to reform, Tristan shuns cigarettes, alcohol and women and adopts a rigorous routine of dawn runs and hard work.

The fortunes of the hard-working Dalby family look set to dwindle even further until almost by accident James discovers the cause of their herd's illness. However, James still needs a push start on other fronts, and Siegfried and Tristan decide to remedy matters with their own expert advice.

Siegfried discovers that a gift given in good faith has brought the deadly foot-and-mouth disease to the dales, and James accidentally hits upon a "sleep cure" for Mrs. Flaxton's poodle.

The waiting room is packed at the Darrowby practice, but Siegfried seems more focused on catching his hard-drinking brother asleep on the job.

The Herriots prepare to move to Rowangarth and another emergency with Granville Bennett.

As James struggles to save the dairy herd in which a friend has sunk all his savings, he discovers a colleague's guilty secret.

England is at war and the time has come for James and Siegfried to join their military units. Their last day at the practice is a busy one and James is repeatedly called out when he had hopes to spend a last, quiet evening at home with Helen. Siegfried surprises James with a small gift. Mrs. Hall also has a surprise announcement for everyone and Tristan receives shocking news from the Royal College of Veterinary Surgeons.

The sport of kings beckons James and Siegfried to the Broughton Races — James in search of a dead cert to raise forty pounds for a Mediterranean honeymoon, and Siegfried in pursuit of a dream job at the track.

James is busy with tuberculin testing but is summoned to the Ministry of Agriculture when the test results don't quite add up. Siegfried has to deal with a dog owner who only believes in strict discipline in dealing with his dog. He also has to deal with dying sheep, but the owners may not have the means to save them. Helen gets a job as a secretary, but James isn't quite sure he approves. Siegfried, on the other hand, thinks it's a wonderful idea. Tristan is less than enthused however when he realizes he will have to take over Helen's duties in the partnership. Mrs.Hall tells Siegfried that she has to leave to help her brother, who is now alone to work his farm.

Siegfried bumps into Mr. Beresford, the manager of the local bank whose dog behaves badly in the car. Tristan woos the lovely Marjorie Simpson and Siegfried meets Sarah Raworth. James treats the elderly Mr. Bailey's dog who has developed a bad case of bronchitis and Siegfried criticizes James when he waives the fee. Siegfried, however, has trouble following his own advice. Tristan rescues a severely injured cat and then convinces James to treat him rather than put him down. Helen promptly adopts him and nurses him back to good health but is devastated when she learns the cat belongs to the Gibbons family. Everyone celebrates Tristan's birthday.

Mr. Biggins tells James about his cowhand, Ned Finch, who goes drinking every night and is drawn to the bright lights of the big city. All James ever sees is an amiable fellow having a quiet drink in his local pub. Mrs. Hall is all aflutter with the visit of Mr. Barge, the loquacious pharmaceutical representative. Mrs.Pumphrey is worried when her new boxer, Cedric, proves to be overly flatulent. James finds a perfect solution. Mr. Beresford's dog is still misbehaving in the car. Siegfried suggest a new sedative, but it unfortunately doesn't have the desired impact.

It's raining cats - literally - when Tristan has to face the terrors of an enormous sow, Our Gracie, and her litter of piglets, who are due to be castrated. When the farm cats take a fancy to the anesthetic-stuffed offcuts, they start to doze off in some very unlikely places. Mrs. Clarke, a very determined old lady, is struggling to keep her farm running until she can hand it over to her young granddaughter, Mary. But she is reaching the stage when she can no longer handle the pressures, even with her elder granddaughter, Katherine to help -- and Katherine is planning to pursue a nursing career in Africa...

James wears his shorts to a visit and is challenged to a race, while Jock, a once champion sheepdog, and delights in chasing cars from the farm.

Christmas at Skeldale House can be a formidable undertaking, what with sick foals, overfed dogs and a skeleton guarding Siegfried's secret hoard of goodies.

Nerves are frayed as Tristan's encounter with an "exploding" bullock leads to a lawsuit, and Siegfried's venture in guinea raising runs foul. Meanwhile, James is sent to assist "on of the biggest boozers in the business."

James musters the courage to visit Helen after she's seen him at his worst. Siegfried resorts to sorcery to aid a gypsy's ailing pony, and a wild ghost chase solves the mystery of the shrouded figure haunting Raine Abbey.

James and Helen's wedding day has finally arrived, though their honeymoon destination couldn't have been further from the Mediterranean. Finally, Siegfried bestows the best wedding present of all.

Deidre and Calum are busy planning their wedding. Deidre discusses her future with Helen, who hopes the couple will stay in Darrowby. However, Calum gets offered a job in Nova Scotia. Siegfried, believing he has forced Calum into applying for the job, hopes he can now persuade him to reconsider.

Life at the Yorkshire veterinary practice continues to challenge the partners, whether by neglected animals or tight-fisted farmers. There are domestic challenges for Tristan, however, when James and Helen play a practical joke with a "Welcome Home" card from an old female admirer. Life is never simple when true love or the demon drink rule Tristan's life, and he is soon in trouble with Siegfried. A new housekeeper, Mrs. Alton, has been recruited by Siegfried to keep a watchful eye on Tristan, who, dispatched to tie up the details of her employment, is delighted to discover that Mrs. Alton is a rather attractive young widow. But this is not the Mrs. Alton that Siegfried had in mind.

Siegfried is determined to make the errant farmers pay their bills.

James' temper is fraying fast -- what with two car accidents in the space of a week, an inauspicious meeting with Helen's family and his rival still lurking around Helen like a "big glossy spider".

The veterinary practice goes from strength to strength, but James fears he has wrecked his chances with Helen after a disastrous first date. Tristan decides that a blind date is all James needs to hone his courtship skills.

Siegfried is perplexed when the usually-caring Grandma Clarke snubs her neighbor, Franco Pedretti, who is the new shepherd on the estate where she is a tenant farmer. It soon becomes apparent that she blames Franco for the untimely death of her son in Italy during the war and the subsequent death of his wife in childbirth.

The return of lambing season brings a boost to Siegfried's spirits, but James, laid up in the surgery, is reminded of the harsher realities of a vet's life.

Helen is finally up and about - only to face the morning after the chaos of Tristan's party the night before.

Tristan and Siegfried meet Roddy, a hobo and his dog who are passing through the area. Mrs. Hall needs to visit sick relatives for a few days and Tristan is assigned chief cook and bottle washer. He also has to do the spring cleaning, cook the meals and put in his time in the surgery. Siegfried is less than sympathetic when Tristan complains. Granville Bennett stops in wanting the vets to care for his dog, Phoebe, who needs an minor operation. He invites James and Siegfried to lunch the next day and James once again over imbibes. Helen practices her first aid skills on James.

Siegfried is laid up at Skeldale with his foot in plaster. His dreams of mouthwatering meals prepared by Mrs. Alton are soon shattered by her regime of a strict diet "for an invalid". Tristan falls for the dark, sad-eyed beauty, Angela Mortimer, Mrs. Pumphrey's great-niece, who has been jilted by her fiance. Fortunately, the demanding dog Tricky-Woo provides an ideal excuse for Tristan to make a number of house calls. James impresses three hero-worshiping locals with his cow-curing abilities, and he learns to value their support when he has to judge the Darrowby Vegetable Show, with disastrous results.

James has his eye on a little semi-detached property coming up for sale, with the notion it would make a pleasant surprise for Helen. Unknown to him, however, Helen has grander ideas. There is trouble from a local farmer, which ironically leads Calum to celebrate his departure from the Herriot household.

James has a crisis of professional confidence while treating a cow with a new drug. Tristan tries to convince a local farmer of the virtues of artificial insemination but Siegfreid only succeeds in enraging the farmer's bull.

Siegfried visits a farm to treat a sick cat and pulls off a brilliant piece of human diagnosis at the same time. He also gets an unexpected visit from the puritan Mr. Hopps -- who does not have an animal with him.

When James treats a sick cat, he finds himself in an awkward position with Mrs. Pumphrey and Mrs.Tibbett. These two formidable and mutually ferocious Darrowby matrons compete both in presents for the invalid and in hounding James for information of the patient's progress.

Harvest Sunday proves to be a trying time for the practice. Seigfreid seizes the opportunity to teach Callum cleanliness by example, forcing him to watch "the perfect operation" on a sick cow. Unfortunately, the operation doesn't go according to plan. When Callum is chased by a bull, James goes to his aid.

There's unusual friction in the Herriot household when 12- year-old daughter Rosie announces that she wants to become a vet -- against her father's wishes. James goes out of his way to show her the arduous, dirty and dangerous side of his work, while Helen thinks he ought to encourage her. But treating her best friend's pony, which has tetanus, may prove too much even for the determined Rosie. Siegried, meanwhile, manages to lose Mrs. Pettinger's kitten Prudence, which escapes from the surgery and hitches a ride to Hull, causing consternation in Darrowby and mirth for Tristan.

Siegfried has become a bit horse shy given his recent experience with Dolly. James has to deal with the very unpleasant Ralph Beamish, an arrogant horse owner who continually ignores his advice. Siegfried visits a local pig farmer and fears his animals may be infected with foot and mouth disease. Mrs. Beck continues to complain about her with the vets bill and is now worried about how her cat might survive a gas attack should war be declared. Germany has invaded Poland and the British government has given Germany an ultimatum to leave or they will be at war.

James meets a pair of elderly twins. Oliver and Roland Strong, rabbit breeder and prize cabbage-grower respectively, have divided the cottage left to them by their mother and have not spoken to each other for 50 years. Now Oliver is convinced that Roland has poisoned one of his rabbits.

Siegfried insists on singing the praises of his new time- management system, a personal diary, much to the annoyance of James. James is particularly put out by Siegfried's successful demonstration to his bete-noir, the redoubtable Mr. Ripley. However, Siegfried's morning is spoiled when he has to deal with Humphrey, an exuberant Great Dane.

Despite Siegfried's insistence that he relax and "cultivate the inner man," James can't shrug off the irritations that often make his professions a dog's life. Siegfried's inner man is cramming for the annual quiz that pits the men of Darrowby against the fearsome Women's Institute.

The Darrowby Bell Ringing Society is suspending its operations for the duration of the war and they have one, final "meeting" at the local pub. James and Tristan go to the bell tower with not unexpected results. The vets have to deal with a series of dog poisonings. They soon identify the farmer responsible, but not before several more animals die. Siegfried treats Joan Clifford's dog Saxon, but the case has very specific implications for her. James treats Mr. Hanson's pigs but it's Mr. Hanson who is most entertaining in that he always speaks at the top of his lungs.

James treats Paul Cotterell's dog Theo, who has been losing weight and is diagnosed with Hodgkin's disease. James recommends that Theo be put down and Paul agrees. James doesn't realize the impact this has on Paul and the tragic results that ensue. James meets Lord Hulton, a hard working farm owner despite his aristocratic background. Hulton takes a liking to a horse that has wandered onto his property from the nearby military depot. At the Billings farm, James finds young calves who are wasting away. He thinks they have ingested an irritant of some kind, but the vets simply can't isolate it.

Siegfried buys a television set, and James has to deal with a man who has cancer.

James and Seigfreid deal with a sheepdog trainer, whose dog is suffering from epilepsy. At Skeldale, two wild cats wander in the garden and Helen takes out food for them. She is hopeful of keeping them but James warns her that they will never come in from the wild.

Buffoon Stewie Brannen, an old friend of Siegfried's, has invited the distinguished Professor Norton to a black tie dinner, and prevails upon Siegfried to host it at Skeldale -- and lend him a dinner suit. But disaster looms when Siegfried and Stewie are called out for a calving, in full evening dress, and James has to hold the fort with an irascible Mrs. Alton.

The possibility of war is on everyone's mind with Helen preparing for the privations ahead and Tristan tasked to tape the windows in the event of bombing. Siegfried decides that they should conserve food and heating by eating their meals together, but Mrs. Hall takes his instructions to economize a bit too seriously. James treats Hamish, a sick dog who requires an operation and Tristan, who is tasked with overseeing his recovery, loses him. The vets forgo a posh evening out to treat a stray dog who has had an accident. Tristan is aghast at Siegfried's attempt to pair him with Deirdre Headingley, one of his crony's less-than-attractive daughters.

Jenny Garston and David Rayner, individually charming farmer and horse-breeder, have been sworn enemies since their earliest school days. When a triple birthday is marred by tragedy it falls to Siegfried to negotiate with the stony-faced neighbors.

Siegfried takes Tristan to task for not mending a hole in the fence. Tristan announces that he now refuses to subject himself to Siegfried's tyranny but he is given 24 hours to mend the fence or face the consequences. Tristan tries to recruit James in his battle with Siegfried, but James will have nothing to do with it. Siegfried comes up with the perfect response. James operates on a sick calf but those assisting him are worse off than the calf. As a result, James comes down with a bad case of the flu. James is also concerned at having to give bad news to Andrew Vine about his dog, given his recent experience with Paul Cotterell.

With Helen still bedridden, there is a dramatic increase in domestic chaos. While James struggles manfully with both chores and children, Siegfried and Tristan praise his noble efforts -- and do precisely nothing. Tristan nfuriates Mr. Bushy, a redoubtable farmer, by treating a dog instead of Busby's cow, by sleeping in, and finally by treating a bull instead of Busby's dog!

The romance between Calum Buchanan and Deidre McEwan flourishes. Siegfried has been hoping that the love affair would quiet down but instead it seems to be going full blast. However, the course of true love never runs smoothly, and it is left to Siegfried to help solve the young couple's problems.

Siegried turns on the charm to teach Tristan a lesson, while James, busy with calving, finds one farmer's traditional Yorkshire hospitality a bit hard to swallow.

Siegfried takes a close friend to task for wasting his own talents as a veterinary surgeon. Ewan Ross -- "the best horse man north of the Humber" has let his career slide gently into the whiskey bottle after the death of his wife. But Siegfried is determined to make use of his considerable skills. A valuable racehorse with a strangulated hernia could provide Siegfried with not only a way of striking back at "vets in Bentleys", but also putting Ewan on the straight and narrow. James, meanwhile, is strangely reluctant to take on responsibility for Mrs. Pumphrey's beloved Tricky-Woo when she announces that she is off to France. But Siegfried caves in under the persuasive skills of Mrs. Pumphrey and Tricky-Woo moves into Skeldale.

The Darrowby Show is a much-anticipated event for the whole community, except for the duty vet. This mixed honor falls to James this year.

Tristan has had a rather late night and Siegfried takes him to task over his bad habits. Tristan announces that he has a steady girlfriend, Deborah Mount and will reform his wild ways. Turns out Deborah's father doesn't know anything about the relationship and may not approve. When he does hear of it, he has serious doubts about Tristan's character. Tristan doesn't help his case with his silly pranks. James has several encounters with a street urchin, Wesley Binks, whom he'd earlier caught stealing. James nonetheless helps Wesley out when his dog contracts distemper. Siegfried reacts badly when the Weeting brothers tell him they are off to join the military.

The vets visit a modern dairy farm and are left to wonder who benefits from the cold efficiency. Miss Westerman returns with her dog Hamish and Tristan tries to avoid her, given that he misplaced her dog the last time she him in the vets' care. She is concerned at the rumors that all dogs will need to be destroyed if war is declared but Tristan sets her mind to rest. The vets agree to spay a cat for a minimum fee, but find they may have gotten more that they bargained for. Siegfried treat Herbie Hinchcliffe's aging horse Dolly and becomes emotionally involved in the case when he has to put