Billie Turf and Dolfie have to stay at boarding school during the summer holidays because their report cards are too poor. Everything goes smoothly...

Billie Turf is a student at Dennenheuvel boarding school. According to his teacher Kwel, he is unreliable, a good-for-nothing, and a liar who can...

Colonel Brulgraag has found the will of King Krijn XXIV of Schiermeeuwen. Whoever finds Krijn's Sword will be the new king. The colonel asks Sjors...

Cor and Jan are two Dutch students who work in a hospital. A smallpox epidemic has broken out, but the country's capital is occupied by the army....

Sjors and Sjimmie have received a magic ring as a thank you for their help to a well-known archaeologist. They end up in the Middle Ages with their...

Uncle Theodor has died and is giving three million guilders to whoever finds the blue diamond. There are two heirs, Mrs. Kakel and Mrs. Ter Beek....