The opera “Nils Karlsson Däumling”, based on the children’s book by Astrid Lindgren, tells the story of a little boy called Bertil who has to spend a great deal of time alone at home. In his loneliness, he tries to while away the time. All of a sudden, he hears a soft knocking. Right beside him, in a mouse hole, lives a little thumbling who is as old as Bertil, but only as big as a thumb. Nisse, as the thumbling is called, lets Bertil in on a secret: if he sings a magic spell, he will become just as tiny as he is. No sooner said than done. Bertil and Nisse become friends, and as Nisse is hungry and freezing, Bertil has some wonderful ideas about how he can help him make a cosy home in the mouse hole... This little opera for everyone aged three and up translates the two different spheres – the world of humans and the miniature world of the thumbling – into a composition for soprano and violin. The violin embodies the magical being. The finely arranged mini-opera enables the children watching to actively participate in the plot through song and play. For the first time, the Kinderoper Köln is also using this mobile opera to visit inclusive and fully residential facilities for children with and without disabilities, with special social difficulties as well as intergenerational groups of children and people with dementia. A supporting workshop programme, where the participants themselves are musically and playfully active, supplements the offer for all young and older people who are unable to attend a children’s opera performance in the opera house.