“But what did they see?” Vi says, her eyes as wide as scallop shells. “What happened?”

Jenny shrugs. “Nobody knows. Except Sebastian. If you really want to know, you’ll have to ask him. Most of the town thought they’d just had a fight and that was that. All I can tell you is that after your dad left, Sebastian Eels stopped working on his book. Just abandoned it. It looks like there won’t be any great work on the malamander after all.”

“But wait,” says Vi, with a frown. “When did this happen? This wasn’t when my dad vanished, was it?”

“Oh no,” says Jenny. “Exactly one year after all this happened, your dad came back. It was midwinter, and he just turned up at the door, all smiles, as if no time had passed at all. He had the manuscript of his book under his arm – a huge pile of papers, all finished and ready to be published, or so he said. And he wasn’t alone. He had a woman with him – and you, Violet, a tiny baby, barely a few months old.”

“A woman?” says Violet. “My mum?”

“Yes,” says Jenny. “I hadn’t met her before, but I always got the feeling your dad had someone. That was the only time I met her, though.”

“What’s her name?” Violet’s voice is so small now we can hardly hear her. “My mum. What’s her name?”

Jenny shakes her head. “I’m really sorry, Violet, I can’t remember. It was a very brief meeting, and I was just amazed to see your dad again. He wanted to show your mother the mermonkey, I think. Took its hat and put it on, playing the fool. He was in high spirits. I got to hold you a moment while all this was going on.”

“But surely you can remember something about her,” says Vi. “What was she like?”

“All I remember,” says Jenny, “is that she was – how can I put it – sciency? Seemed to belong to a different world from your dad, I mean. He was all dreams and wild ideas while she was more … sciency.”

I nearly drop my mug. “Exotic Erratics!” I cry.

Vi and Jenny look at me in amazement.

“Oh, bladderwracks!” I say. “I’m such a ninny! Vi, I completely forgot to tell you! I found something out. I found out who your mother is.”

And I tell them about my phone call.

“The Natural History Museum?” Jenny gives me a disbelieving look. “Herbie, are you sure?”

“I swear it’s true. That’s what the man said.”

“But what’s this about ‘Exotic Erratics’?”

“Well, that’s what he said when he answered the phone. Then when he heard it was a stranger on the line, he changed it to something longer. Something about a crypto and a zoo…”