Ester and Klaus, whoever they were, marched onwards. Max followed. They kept up a fast pace, and it was hard work, but the pleasure of finding her first proper clue pushed her on. Surely, if these two were lying about Klaus, they must be up to no good.

At the edge of the park they came to an enormous ice rink, speckled with figures in bright jackets who criss-crossed over it in sweeping arcs. A bridge over the ice led them to an old castle at the side of the rink, sprouting turrets with peaked red caps, and at its gate there was a cluster of wooden huts selling hot food and heady spiced wine. They stopped. Lunch.

Max was starving: lunchtime had been and gone ages ago. She bought something doughy and warm and covered in cheese from one of the huts. Clutching her paper bag, she retreated to a picnic table that was right next to Ester and Klaus, but hidden behind a large tree. She could hear Ester loud and clear; above her, a squirrel was hiding under its own tail in alarm.

Ester was complaining about something in German, and Max couldn’t follow at all. So she took the opportunity to update her notebook. On Ester’s page she wrote:

Visiting Istvan Marek. Who? Why? What was she trying to sell?

And on Klaus’s she wrote:

Ester Rosenkrantz is an only child. Klaus claims to be her nephew. Who is he really? Why is he lying?

She was lost in her thoughts for a while, until quite suddenly there was a frenzied croaking from the other side of the tree, and Ester went scuttling away at a startling speed across the grass. Max peered around the tree trunk to see what had happened, and saw Klaus trying to encourage an enormous spider on to his hands. The spider was not impressed. It hurried away across the table, looking quite a lot like Ester.

Even when Klaus had managed to get rid of the spider, Ester refused to return to the table. She was shaking and croaking gently to herself. Sighing, Klaus returned to the table to pick up both their cases and Ester’s bag of pear drops, and went off to comfort her.

Then they were off again, and Max had to scoop up her notebook and trot after them.

It was only as she left that she noticed Celeste. She was sitting at another picnic table, a little way off, staring into the distance. As usual. Max watched her, waiting for a sign of life. Why was she always just sitting around staring? That was something that people in films did, but not real people with brains to get bored and fingers to get cold. What was she up to?