Lucia gave a little shudder again. The TricTrucTrackers were silent, thinking, as the Tracboat glided on through the net-sky.

Then Fromage spoke up.

“But surely… zis Trinth, ‘e knows we are on a mission of mercy!” he said twirling his whiskers round and round so they were like corkscrews, then letting them go so they pinged! back straight again. “Will ‘e not WANT to ‘elp us?”

“No!” said Walpurgis. “No, he won’t! Not unless we follow EVERY rule!”

“Well, what are these rules?” asked Dot.

“Well… for a start, everyone entering a TZ must have an up-to-date Tzonecard” said Hombellyton. “And guess who lost ours?”

Walpurgis turned round, wagging a paw at his companion.

“I did NOT lose it!” he said angrily. “I know I was in charge of it, but it wasn’t I who lost it! Somebody else must have! It’s GOT to be in this Tracboat somewhere, if only we could find it.”

“Gently” murmured Carmeramalita, always the peacemaker. “Gently now boys!”

“Well we’ve got to” said Eldenbeam. “Or we’ll be stopped before we’re started!”

“Can I help?” asked Wizzie. He’d jumped up with his front paws on one of the computer screen tables, and his feathery tail was swishing from side to side.

“How can you help?” asked Katzilow – rather rudely, Dot thought.

“Well maybe I can smell it out” said Wiz, his eyes dancing and his pink tongue curling out of his mouth in excitement. “My cousin Merlyn works at Heathrow Airport, and he finds stuff right inside people’s suitcases, when they try to bring bad things into our country. And they’re always under a pile of clothes, or even hiding inside the lining or the handles of suitcases. If he can do it, so can I! We have good noses in our family!”

Dot bit her lip. It seemed to her that her friend was taking on too much! But she didn’t want to put him off, so she backed him up.

“Wiz can find anything!” she said loyally. “All he needs is a sniff with the last person to touch whatever was lost!”

“Well who had it last? We’re not sure” said Walpurgis.

“Definitely you!” said Hombellyton, wagging his funny flat spoon-shaped beak.

“Oh, that’s right” said Walpurgis. “Blame me! When there’s any trouble, land it on old Walpurgis! He’ll take the stick! He’s the one who carries the load. He - ”

“Look!” said Dot. She couldn’t stand this any more. “We’re supposed to be finding Mr Mouse! It won’t do any good if you all keep arguing, and... and throwing hissy fits like this!”

Carmeramalita giggled. “Go girl!” she whispered to Dot.

“A hissy fit?” said Walpurgis, stopping his moaning in mid-sentence. “Now that is an interesting phrase! What does it mean?”

“It means what you were just doing” said Dot, who was already feeling a bit scaredy about jumping in like that.

“Very good!” chuckled Walpurgis. His mood had changed completely. “I like that very much!”

“Me too!” said Eldenbeam.

“Hissy fit!” smiled Katzilow. “I’ll remember that!”

Ho ho haa-de-ha, went Hombellyton. (That’s the way TricTrucTrackers laugh.)

Well that’s one way of stopping them having all these arguments, thought Dot. Find some funny phrase or word they haven’t heard of. At least I can do something to keep us going now!

“Who shall we start with then?” said Dot. She really wanted to get on! What they needed was her head teacher Mrs Rudman – she’d soon have them hard at work, no doubt about that!

“Better be me!” said Walpurgis, still chuckling to himself.

He put out a paw, and Wizzie came forward to smell it.

“Mmm!” he said, sniffing away. “Shepherd’s pie… a computer mouse… those ‘Comber’ things up in the front… a pair of glasses… and… and something made of a kind of rubbery stuff.”

“That’s it!” said Walpurgis excitedly. “Well done Wizard! The Tzonecard is made out of plimdorodum, a special kind of internet material that bends and never breaks! It is rubbery!”

“BeZEEET! BeZEEET!”

It was an alarm sound – and it came from the Tracmapper. Walpurgis turned and ran up to the glowing globe above a funny blobby thing that was kind of a keyboard and kind of wasn’t. The globe was pulsing a strange grey-gold colour. He peered at it for a moment then turned back to his friends, his face deep in worry.

“We’re losing the optimum – our best chance of getting near where Mr Mouse is!” he said. “Wizzie – we need you to find that Tzonecard now!”