Film tells Allan Karlsson, a famous explosives expert, is retiring. There is a birthday party which is held to celebrate his 100 years old. But he is not interested in snacks, champagne, he quietly climbs out the window and disappears. He pulls a huge suitcase on the road without knowing that he is holding a money suitcase of drug smugglers. The memories of a glorious return with the making of explosives, the pride that he had dinner with President Harry S. Truman, met Prime Minister Winston Churchill ... And so he goes until the drug smugglers chase up..