The story starts when Mrs. Pumphrey, a rich lady takes her dog out for a walk. A nearby veterinary doctor who knows the lady sees the dog and is shocked as he sees that the dog looks like a bloated sausage with a leg at each end. He advises her to stop giving him unhealthy things to eat but Mrs. Pumphrey is not able to refuse him. Soon he falls sick and the doctor is called. The narrator, Mr. Herriot then somehow takes Tricki, the dog to the hospital even though he knows that Mrs. Pumphrey is not ready to leave her dog and nearly fainted just by hearing these words.Then he takes the dog along and puts a bed for him in his surgery. The dog doesn't move much nor eats anything for the first two days. On the second day he looks around and whimpers a bit. He wanted to go out on the third day and started playing with the bigger dogs when he was taken out. He also licked the bowls of other dogs clean on the third day.

Then his condition started improving very fast. He started fighting for his meals with other dogs. Then when this news reached Mrs. Pumphrey, she started sending him eggs as she thought that Tricki was recovering from an illness and needed energy foods. Mr. Herriot and his partners started eating those eggs for morning breakfast. Then for improving Tricki’s blood, Mrs. Pumphrey started sending in bottles of wine which was again consumed by Mr. Herriot. He used to take two glasses before lunch and some more glasses while having his lunch. Then when she started sending in bottles of brandy for Tricki that was the time when Mr. Herriot thought that he would really like to keep Tricki as a permanent guest in the surgery. Mr. Herriot used to be really happy someday by having two extra eggs every morning. Then having few glasses of wine in the afternoon and closing the day by having brandy at night. But then he took a wise decision and called up Mrs. Pumphrey as she was really worried and on this side Tricki was ready to be taken back home. Tricki was really happy to see his mistress and jumped into the car. Mrs. Pumphrey said that she won't be able to ever thank him for what he had done and also, that his surgery had been successful as Tricki was now cured.