Ture Sventon may be the most skillful private eye in the country. Problem is, no one knows it given his lack of cases to prove himself. Jan and Kristina Hjortron spend their summer with their aunts in the quiet village of Lingonboda. Suddenly, the stillness is interrupted by a strange man. The aunts later receives a threatening letter from a Vilhelm Vessla. The letter prompts the aunts to contact Sventon.

A humble man called Mr. Omar calls on Sventon and offers him a flying carpet. After a test flight he decides to buy it but must raise some money to do so. Together with Sventon and Ms. Jansson, the secretary of Sventon, Mr. Omar drinks coffee and eats a cream bun.

The children's aunts are worried about the threatening letter and its writer. As a result, they make Jan and Kristina stay indoors all day. Meanwhile, Sventon is on his way to Lingonboda.

After overhearing the villains plans, Sventon sets a trap involving the aid of Jan and Kristina.

Sventon discovers why his plan had failed and quickly comes up with a new one.

To his horror, Sventon's plan backfires when he discovers stowaways on his flying carpet. Vesslan and his partner tries to escape.

With the Lingonboda-case all wrapped up, Sventon is now wanted by everyone. His reception room is filled with people wanting him to find all sorts of missing objects. Tired of it, Sventon decides to take a vacation to the Arabian desert and his friend Mr. Omar. But for his trip to be fulfilling, he needs a way of transporting his cream buns. He visits engineer Hjalmar Hjortron, expert on refrigerators, but gets more than he asked for.

Sventon spends an evening at the Hjortrons. Deciding to help the engineer, he leaves with the groundbreaking refrigerator "Nordpolen". He is not alone, however.

"Nordpolen" is filled to the rim with cream puns when Sventon heads up to purchase some travel equipment. On his return he discovers a theft. He quickly learns the whereabouts of the thief and sets off. Once again he is surprised when he is not alone on his carpet.

The Hjortron children and Sventon arrives at Mr. Omar's tent, finding him in distress. They visit the town of Djof in search for the thief.

The children disappears and Sventon makes a discovery.

Sventon and Mr. Omar go undercover as bakery employees.

Sventon puts his plan into action, hoping to bring back the refrigerator, the children, and the camels all at once.

Returning to Mr. Omars tent, he and Sventon patiently waits for the last piece of the puzzle. Meanwhile, a caravan makes Mr. Omar nervous.

Lord Hubbard pays a visit to Sventon after strange things happening in his house in London. While he is at Sventon's office, Mr. Omar turns up with a sore throat.

Returning to London, Lord Hubbard shows his guests Sventon and Mr. Omar the house. A Mr. Smith from London's Joint Cat Friends visits and wants to take the cat with him.

An intruder wakes the house but he escapes to everyone's astonishment. Mr. Smith returns for the cat and avoids Sventon's trap.

The plot thickens as Mr. Smith returns to his hideout. Sventon receives help from the local police.

Christmas has arrived in Stockholm and jeweler Eriksson prepares for the holiday sales. A break-in and a dirty hat interrupts the joyous Christmas spirits.

Jeweler Erikssons mother arrives and key chains go missing. Mr. Omar reads about Stockholm whilst sitting at his tent in the Arabian desert.

Sventon listens to jeweler Erikssons worries. Later, Christmas presents are given at the Sventon office.

The jewelry store is in danger. Sventon and Mr. Omar must hurry to the scene, only to be mistaken as part of the robbery gang.

Arriving at the robbers hideout, Sventon and Mr. Omar tries not to be recognized as they serve Christmas dinner to the crooks.

Jewels are returned, criminals are locked up, and Sventon reveals his method to everyone.