Luke has to write an essay on prehistoric people for the school. To help him, Miss Moon brings the statue of Honk to life in the Science Museum so Luke can interview him. The conversation turns out to be very one-sided, because Honk does not bring more than "Honk" over his lips and Luke does not seem to understand him. When Honk sees Miss Moon, it happened to him. He instantly falls in love with the nanny and kidnaps him. Luke and Lola try to stay on track.

By mistake, the baroness gets Miss Moon's magic key, which makes her magically change places. The Baroness imagines her goal is to be able to finally expose Miss Moon as a witch and enlighten Lady Pop about her nanny. Luckily, Miss Moon has a duplicate key that she and the kids use to stay one step ahead of the baroness. An exciting hunt through space and time begins.

A heat wave makes New York glow and the zoo's water has to be rationed, so that none of the animals has to suffer from thirst. But then an unknown thief steals the water from the zoo's own cistern and it comes to a state of emergency. To get water as fast as possible and to prevent the animals from dehydrating, Miss Moon creates a magic diviner that will show them the way to the stolen water. When the children find the thief, they are not surprised.