Allan Karlsson, resident of a nursing home in a small Swedish town, is about to be celebrated at his 100th birthday party with the press, the mayor, and the entire nursing staff and fellow residents in attendance. But Allan really isn't interested (and he'd like a bit more control over his alcohol consumption), so he decides to escape. He climbs out the window in his "pee slippers" and embarks on a hilarious and entirely unexpected journey. At the same time we discover Allan's larger-than-life back story: not only has he witnessed, Zelig-like, some of the most important events of the twentieth century but he has actually played a key role in them. Starting as an explosives expert, he finds himself involved in the development of the atomic bomb and in his travels throughout the world, shares meals and more with everyone from Stalin, Churchill, and Truman, to Mao, Franco, and De Gaulle.