WHEN WE GET BACK to the hotel, Violet heads for the side passage so I can let her in through the cellar window. I call her back.

“Not this time,” I say. “I think you should come through the front door like everyone else.”

“Won’t they see me in Reception?” says Vi.

“Seriously?” I look at her. “After everything we’ve been through, you’re worried about that?”

“But won’t I get you into trouble?”

I look at her some more. “Er, you’ve been getting me into trouble ever since you got here, remember?”

So we walk up the steps and through the great double doors of the Grand Nautilus Hotel, side by side.

It’s as we’re lifting the counter in my cubbyhole that Mr Mollusc sees us.

“Herbert Lemon!” He strides over, bristling his small moustache. “It is not permitted to take guests down there. Please attend to the young lady in the correct manner and —”

Then he stops, probably because now he has a good view of Violet. I try to imagine what he sees: a wild-haired girl with a scratched face, in a too-big borrowed coat and a ratty pullover. A girl with a harpoon hole through her clothes, her mother’s boots clogged with sand and seaweed.

I see the vein start to throb on his temple, right on cue.

“What is the meaning of this?” the hotel manager hisses, lowering his voice in case any of his precious guests are near by.

“Violet’s a friend,” I say. “There’s nothing in the rules to say I can’t have a friend over.”

Mr Mollusc grinds his teeth as he jabs his finger at me. “I don’t understand what you’re even doing here, boy. Didn’t Her Ladyship fire you this morning?”

“Fire me?” I chortle. “Lady Kraken didn’t fire me. In fact, she asked me to do her a special favour. She asked me to keep my eyes open for any dodgy business going on in her hotel.”

“But –” Mollusc is quivering with rage now – “you are the dodgy business in this hotel, Lemon! YOU!”

“I think she had something else in mind,” I say, straightening my cap and fixing the man with my best stare. “Like, for instance, someone stealing things from my Lost-and-Foundery.”

“Stealing?” Mr Mollusc says, the first hint of doubt creeping into his voice.

“Yes, stealing.” I dial the stare up a notch or two. “I mean going down into my basement when I’m not there, taking suitcases that don’t belong to you and then signing them out as if collected by family. That sort of stealing.”

Mr Mollusc passes his hand through his wispy hair. There is suddenly a bead of sweat in his horrible moustache. “Oh, I see.” He forces a smile. “Why would anyone do such a thing…?”

“For money, I expect,” says Violet. “The worst reason of all.”