In a laboratory in Sweden before Christmas 2020, the scientists Anna-Carin Colt and Vilgot develop an artificial black hole to be used as an energy source. The black hole is accidentally released and ends up in the rafters of an HVB home where the orphan Mira lives. Mira is soon to be adopted, but does not want to be separated from her friend Galad. Exactly 100 years earlier (in 1920) and in the same building, then a mansion, the upper-class girl Rakel Colt is getting ready to be photographed with her family. Mira and Rakel both stumble upon the black hole and are involuntarily pulled in by it, switching bodies and time periods.
