Kareltje asks Johnnie to have someone over for a night against a substantial pay. Johnnie doubt first because he has bad experiences with the guests from Kareltje, but when he hears that it is a "she", he agrees.
"She" is not a man but a horse. A stolen horse to be exact. The next day the animal will be picked up by someone. The man who would get the horse is arrested. The Flodders now have a stolen horse in the house.
When Sjakie comes along and asks whether Johnnie and Kees want to work on a "Sinterklaas-intocht" the Flodders see an outcome.