Based on Bjarne Reuter's 1975 juvenile novel, even broader comedy strokes are employed in the film version, but bright spark Bertram is still at the center of things when a nice but dubious uncle (he has a criminal record) takes all the kids of a working class family, hit with bad luck, away on an outing. A plot is cooked up to kidnap some rich kid. It works at first, but soon things get out of control.

Done back-to-back with "Kidnapping", 1982, this family entertainment continues the saga of little Bertram's rather erratic and not always law-abiding family. Parents, chief schemer Uncle Georg, Bertram and his swarm of siblings all get into hot water when Betram's slapdash kindergarten artwork is somehow being mixed up with a famous painting from a museum.

Bertram and his family seek compensation after being swindled by a shop manager. George, a relative of Bertram's, has an idea when he discovers that the shop will display the most valuable diamond in the world.