"I tell you what, though. The timing's a bit odd."

"What do you mean?" he asked.

"Well, if the accident happened a year ago, why wait until this morning to spray graffiti on the wall?"

Graham sipped his drink. "Kylie mentioned a judge. As you know, in cases of accidental death there has to be an inquest. There must have been some sort of inquiry, but these things can take months. It might only just have been completed."

"What difference would that make?"

"It's conceivable that the graffiti artist was hoping to obtain what they considered to be justice through the official channels. If Mr Monkton was cleared of all blame, that person might have been provoked into taking matters into his or her own hands."

I was impressed by Graham's reasoning. "OK," I said. "That sounds about right. Kylie seems convinced it was Mr Monkton's fault, doesn't she? And as far as we know, lots of people agree with her. Who was that other man she mentioned this morning a Archie Henshaw?"

"Yes." Graham nodded. "If we could get access to a computer we could probably find out who he is. But I don't see how we can manage that just now."

I drained my c.o.ke and then said, "I tell you another weird thing about this morning. That girl Zara turning up and freaking out Mr Monkton. Didn't someone say that the tiger suit had been got rid of?"

"Yes."

"They also said she was new, so she can't have known about it. Someone deliberately put it in her office." I crushed my c.o.ke can between my palms and threw it into the recycling bin. "I wonder if we can talk to her."

After we'd eaten, we walked back towards the manor house in search of Zara. She wasn't hard to find: she'd ditched the furry outfit, but her dyed orange hair was as bright as a Belisha beacon. We could see her from way across the front lawn, sitting in an open-sided yurt surrounded by a sea of Brownies. When we got closer, we realized she was doing a hands-on creepy-crawly session. Or at least she was trying to. Her audience was a little on the excitable side, wriggling around on the benches like an infestation of yellow maggots. There was a load of giggling and shrieking and girls-being-girlie-girlie over the insects, and even though she was using a microphone, Zara's voice was too weak to cut through it.

"What I'm going to show you next is a special kind of insect all the way from the rainforests of Madagascar," she said, her eyes widening in an attempt to convey the Marvellous Miracles of Mother Nature.

"Where's that?" demanded one Brownie.

"Er... It's near Africa. They're quite big a when they're adults they can grow to about eight centimetres. They're excellent climbers and can even walk up a sheet of gla.s.s."

"Big deal," said another Brownie witheringly, and the girls either side of her giggled.

Zara took out a box labelled MADAGASCAN HISSING c.o.c.kRAOCHES and the squealing reached a new intensity. One of the Brownies chose that moment to jump up, hands clapped over her mouth as if she was about to be sick. Brown Owl reacted like greased lightning, whipping out a paper bag and clamping it to the unfortunate girl's mouth. But in doing so she caught Zara's elbow and the box of c.o.c.kroaches went flying.

Fifteen large c.o.c.kroaches landed on the heads of fifteen small Brownies. The girls leapt hysterically off the benches, flapping at their hair and flicking the insects to the floor. The poor bewildered c.o.c.kroaches scuttled in all directions. Zara tried frantically to retrieve them, but she didn't have enough hands to scoop up more than one or two before the Brownies stampeded from the yurt. When the last of the yellow-clad squealers had fled across the lawn, she looked ready to burst into tears. It was too good an opportunity to miss.

"Do you want some help?" I asked.

"Oh yes, please," Zara said gratefully.

So Zara, Graham and I spent the next twenty minutes rounding up hissing c.o.c.kroaches.

There's something bonding about hunting creepy-crawlies, and we got quite friendly as we crawled under the benches together. Miraculously we managed to locate all fifteen, although I have to say that one or two looked suspiciously like common-or-garden pests rather than their exotic cousins. After they'd been safely returned to their box, Zara rewarded our efforts by buying us another c.o.ke in the Ballroom Cafe.

"What a day!" she said. "And it won't be over until nearly midnight. I'm supposed to be a teddy bear at the staff party tonight. I'm entertaining the kids a and some of them are hideous." She looked at us, suddenly aghast. "Oh, whoops a your parents don't work here, do they?"

"No," I a.s.sured her. "We're visitors."

"Oh, right. Didn't I see you two first thing this morning?" she asked, opening her drink.

"Yes," I said, adding pointedly, "when you were in the tiger suit."

"That suit!" she exclaimed, banging her can down on the table so that the c.o.ke frothed out. "That was so strange. Where did it come from? That's what I want to know."

"Do you?" I said as casually as I could manage.

Graham asked neutrally, "Why were you wearing it?"

Zara's brow furrowed. "It was in my office this morning with a memo from April a Mr Monkton's secretary a saying it was a replacement for the bear outfit. I have to dress as a teddy when we get big crowds in. It keeps the toddlers amused, you see."

"Right."

"But then April said she didn't write any memo. So someone must be playing a stupid practical joke," she said miserably. "Laughing at the new girl. I suppose they think it's funny."

"Any idea who?" I asked.

"No," Zara replied, sniffing. "It might be one of the keepers. Some of them have a very odd sense of humour."

"Maybe it was the same person who sprayed the graffiti on the wall?" I suggested.

"Do you think so? But I didn't understand that either. Who's S.M.?" Zara looked puzzled.

"We presume that he was the keeper who died last year: Sandy Milford," said Graham.

"Sandy Milford?" Zara echoed. "Is that who it's about?" She sat back in her chair and sighed. "I've heard people talking about him. His sister's one of the keepers."

"Kylie?"

"Yes, that's right. And Charlie Bales a Kylie's boyfriend a is his wife's cousin, I think."

"Really?"

"Oh yeah a and apparently his wife used to work here too, before she had kids. They all seem ever so close. That accident must have been really traumatic for everybody." Zara sounded wistful. Lonely. An outsider excluded from the pack. She finished her drink. "Better get back to work," she said. "I've got a session with the Cubs in a minute. I hope they're better behaved than the Brownies!" She flashed us an anxious grin and left, but her words hung in the air.

"Traumatic for everybody," Graham repeated thoughtfully.

"Yes," I said. "But is one of them traumatized enough to take revenge?"

the scent of death.

After the lunch break Graham and I made our way to the Frozone with a growing sense of unease. The animals seemed strangely tense too. As we walked past the Savannah the zebras kicked out at each other, ears laid back, yellowed teeth snapping. In the Rainforest the monkeys screeched and squabbled. Despite Kylie's effort with the log and the aftershave, the tigers paced restlessly.

"Do you reckon someone wants to hurt Mr Monkton?" I asked Graham.

"Statistically speaking, the writers of anonymous notes rarely resort to physical violence. I would a.s.sume that the same rule applies to graffiti. As we know, the object of the exercise is to terrorize the victim."

"Well, it worked. The poor man was scared stiff this morning. But who did it? It has to be an inside job, doesn't it?"

"I would have thought so," ventured Graham. "Mr Monkton certainly isn't popular with the protesters outside the gates, but it seems unlikely that they'd be concerned about the death of a keeper."

"And they wouldn't know the effect the tiger suit would have, either, would they?"

"No," Graham agreed. "Which all points to the culprit being a member of the zoo staff."

We were due to meet our next keeper at 2 p.m. by the polar-bear pit. At five to two we were both standing there watching the animals dozing on a concrete rock.

"I don't know," I said, surveying the enclosure. "You can't help feeling that those protesters might have a point. It's not exactly the Arctic wilderness, is it?"

"It's a complex ethical issue," Graham replied sagely. "If global warming continues at its present rate, a zoo might be the only alternative to extinction."

We didn't have time to debate the matter any further, because just then Charlie Bales appeared, clocked our green overalls and said, "You're the Behind the Scenes kids, right?"

We nodded.

"OK. Follow me."

Kylie's manner had been brusque, but Charlie's was positively menacing. The first thing he did was take us into the little kitchen near the polar-bear pit. Reaching up to a high shelf, he pulled down two small bottles and gave one to each of us. They were the old-fashioned sort a square-based, heavy, with a large gla.s.s stopper a the kind of thing you might see in a Victorian chemist's or a Mad Science Lab. Mine was half full of clear liquid. There was no label telling me what it contained.

"Have a sniff of that," he urged me. "Go on. Take a deep breath."

I didn't like the way his eyes were glinting, but I couldn't think of any reason to refuse. Hoping it might be aftershave, I pulled out the stopper and did what I was told.

It was only with a monumental effort that I managed to stop myself emptying my lunch and breakfast and everything else I'd ever eaten onto the tiled floor. I have never, ever smelt anything so utterly stomach-churningly disgusting. It literally made my head reel and I had to sit down on the nearest chair to recover.

Charlie Bales laughed nastily, and Zara's words about keepers with an odd sense of humour drifted through my head. I'd have bet all my pocket money that he'd been the one to put that suit in her office.

I couldn't speak, but Graham a who'd caught a whiff even though he hadn't breathed it in a said faintly, "What is that stuff?"

"Putrescine," said Charlie.

"Putrescine?" echoed Graham. "As in putrid? Meaning rotten? Decomposed?"

"You've got it."

Graham and I exchanged a worried glance. We were at the mercy of a total madman. Graham's solution seemed to be to keep him talking until we could escape.

"But why...?" he began.

"The bears love it," said Charlie. "I soak logs in it from time to time. Keeps them very busy, it does..." He leant forward until his nose was almost touching Graham's. "It's the scent of death."

"Environmental enrichment?" Graham's voice wavered back at him.

"You're learning," said the keeper gruffly.

"And what's this one?" Graham asked politely, holding up the bottle Charlie had put in his hand. I noticed he was careful not to remove the stopper.

"Cadaverine," Charlie answered promptly.

"As in cadaver? Corpse?"

"Yep."

"Ingenious." Graham was rapidly running out of conversation ideas. "Very clever. Lovely. Hmm..."

There was a short silence. I was still feeling too sick to speak, but fortunately Charlie decided he'd had enough of his little joke. He took the bottles from our unresisting hands and put them back on the shelf.

"I won't be giving them either of those today," he said, winking at Graham. "You're off the hook. They had all they needed to eat this morning. You can help me with the penguins instead."

Feeding the penguins was fun. They were all different shapes and sizes, from the king penguins, that came up to my waist, to the little rockhoppers, that barely reached my knees. One was really tame and waddled along behind us, taking fish from our hands. After that we got to feed the fur seals, so all in all our afternoon with Charlie proved a lot more enjoyable than we'd expected at the outset.

Our Behind the Scenes tour ended at 4.30 p.m. and just as we were washing our hands in the kitchen, April appeared and said to Charlie, "Mr Monkton wants you to sort the bears out before tonight." Without even glancing at us she added, "Give them a scatter feed. Throw in a couple of logs, too a he wants them kept busy this evening."

A look of irritation pa.s.sed across Charlie's face. "They were fed this afternoon," he said, glancing pointedly at his watch. "I haven't got anything prepared."

"Well, prepare something now, then," April said brusquely. "They'll be disturbed by the party and Mr Monkton doesn't want them pacing. It might upset the hotel guests."

"I finish work in half an hour," Charlie protested.

"You'd better be quick, then, hadn't you?" replied April coolly. "Mr Monkton can't afford to pay you overtime. And he'll be down to check on them before the party, so don't take any short cuts."

April walked away, oblivious to the furious glare Charlie Bales was burning into her back. Graham and I finished washing our hands, muttered a quick good-bye and slipped out of the kitchen as fast as we could. Just as we were closing the door, Charlie's walkie-talkie crackled into life.

"You nearly ready to go?" a woman's voice asked.

"No," he replied sourly. "Sorry, Kylie."

"Oh, OK. I'll get a lift home with Angie, then."

"You better had. I'll be stuck here now until the party. April's just said Monkton wants me to feed the bears again."

"What, now?" Kylie sounded as angry as Charlie.

"Yeah. Just throw in a couple of logs, she says."

"Like you can buy them in the supermarket!" Kylie sighed. "That man's got no idea, has he?"

"Well, I hope I don't see him before the party, that's all I can say. The way I feel right now, I might just do him an injury."

I looked at Graham. He pursed his lips. We didn't like the sound of that at all.