Because their mother works night shifts and their father lives far away, Merle and Moritz get a new nanny to take care of them. Her name is Gesine Wolkenstein, she has thin lips and eerie eyes that change colour. First they are green as the grass, then black and finally light blue and transparent. Of all people she is the one supposed to tuck the children in at night! But thankfully, at night, there comes Ms Wolle to the rescue.