The book is about identical twin girls whose parents separated them in infancy upon divorcing, only to reunite at a summer camp years later before switching places.

In 2014, the book was faithfully retranslated into English by Anthea Bell, featuring Walter Trier's illustrations and republished in the United Kingdom and Australia by Pushkin Press as The Parent Trap, after Disney's adaptation.

Luise and Lottie are then allowed to go into the village, where local photographer Mr Josef Eipeldauer takes pictures of them to send home.

The sisters deduce that they had lived together until they were two years old, when their parents divorced and split them up just as their mother, Luiselotte, divided her own first name to give her daughters theirs.

For the past weeks, Luise and Lottie have been exchanging notes on how to impersonate one another, as they secretly plan to switch places and each spend time with the parents they have never known before.

It is revealed that whenever Ludwig holds a concert in Munich, Luiselotte secretly buys a ticket and watches him perform, aware that he is unhappy despite his successful career.

In Munich, Luise messes up while trying to cook like her sister, but her mother happily helps her "little housewife", her nickname for the real Lottie, who always keeps house whenever Luiselotte works overtime.

Shocked by the news, Lottie individually begs her father and Irene to call off their engagement, but both adults refuse, with the latter intending to send "Luise" to a boarding school once the wedding is over.

Shocked by the pictures, Luiselotte leaves work to go to Miss Linnekogel, whom she tells of the split custody arrangement and of her suspicions that the twin living with her is actually Luise.

Since switching places, the twins themselves have been secretly corresponding with each other; Luise, who is now aware of her father's relationship with Irene, becomes concerned because Lottie has suddenly stopped sending her letters.

The amused headteacher, Mr Killian, says the sisters' actions have reminded him of the time he taught Sepp and Anton, identical twin brothers whose impoverished parents enrolled them as one boy, making them take turns going to school as such.

As Luise's classmate Trude, who was present at the time the twins met at camp, tells the other students and their teachers the whole story, the Palfy family takes a taxi home, passing by Irene along the way.

Bell's translation is more faithful to the German original in line with the publisher's aim of introducing children to stories from different languages and cultures.