Before doing so, he takes a look at the postcard and sees it is addressed to a king, saying that his son will soon be coming home, recognised by his possession of a golden apple.

Upon arriving, Bosse is told that his real name is Mio, and that he is the son of the king and thus a prince of the land.

As he explores his father's kingdom, he meets and befriends other children, but also learns that not everything in this world is as wonderful as it first seemed.

In the American version, Mio is first called Karl Anders Nilsson, nicknamed Andy, and Jum-Jum's name is Pompoo.

[1] Central themes in the story focus on friendship granting strength to endure hardships, that it is sometimes necessary to leave a safe situation and put oneself at risk for a greater cause, and that evil often coincides with unhappiness.