The Dough Must Go On (Oxford Tearoom Mysteries ~ Book 9)

by H. Y. Hanna

  “Imagine how we felt! We were sitting in the audience, wondering where you were… and then the next thing we knew, all hell had broken loose. All we could see were people running backstage and all we could hear was this terrible screaming—”

  “That screaming was me,” I said, embarrassed.

  “Yes, Cassie told me that you’d had quite a nasty shock,” Seth said with a sympathetic look. “Hardly surprising… finding a dead body like that.”

  “It wasn’t so much discovering a dead body as seeing the way her face smashed to bits when it hit the ground…” I shuddered at the memory. “It was horrible, Seth! I just can’t get the image out of my mind. I mean—how can flesh just shatter like that?”

  “Ah, well, you see, liquid nitrogen is a cryogenic fluid—its boiling point is minus 195.79 degrees Celsius or minus 320 Fahrenheit; that’s only 77 kelvins above absolute zero, which is when all thermal motion ceases. And at that temperature, you encounter the Ductile-to-Brittle Transition. Even materials which are ductile at normal room temperature can become highly brittle when super-cooled, due to the change in the directionality of the chemical bonds, and with the high percentage of water in organic matter, it’s hardly surprising that brittle fracture occurs—”

  “Seth!” I said in exasperation. “In English, please.”

  “Oh. Right.” He gave me a sheepish grin. “Basically, living tissue such as our flesh is made up primarily of water, so when it comes into contact with something as cold as liquid nitrogen, it freezes completely, and we turn into something a bit like an ice sculpture. And ice is very brittle, as you know. Of course, a very dense object wouldn’t break unless an extreme force was applied—that’s why her entire head didn’t shatter—but thinner objects, such as her nose or the other features on her face, would crack and crumble easily if put under stress, such as when her face hit the ground.”

  “But what about the murderer?” I asked. “Wouldn’t he or she have been affected too? I mean, they must have had to shove Lara’s head into the cauldron and hold it immersed in the liquid nitrogen for a few seconds, until she… er… froze solid. Wouldn’t their hand be affected too?”

  “Well, they could have worn insulating gloves… but even if they hadn’t, they would probably have been protected by the Leidenfrost effect.”

  “The what?”

  “It’s a physical phenomenon which occurs when a liquid comes into contact with something that’s much hotter than its boiling point. Part of the liquid evaporates and forms an insulating vapour layer around itself,” Seth explained. “You see it sometimes when you drop water on the hotplate on an electric stovetop: you’d expect the water to evaporate immediately, wouldn’t you? But instead, the drops just move around on top of the hotplate for a few moments.”

  “Oh yes, I’ve seen that!” I cried. “I always thought that was weird, the way they skitter around.”

  “Well, the drops are being protected by an invisible layer of vapour between themselves and the hotplate. The same thing happens if you plunge your hand into liquid nitrogen for a short while—the nitrogen immediately in contact with your skin vaporises, forming a cloud of vapour which coats your hand and protects your skin from the freezing effect of the rest of the liquid nitrogen. But the vapour doesn’t last forever—so if you kept your hand in there, after a few minutes, it would freeze solid.”

  “You know, I’m wondering if most people know all this stuff. I mean, it might help to narrow the suspect list,” I said excitedly. “Surely someone would only use liquid nitrogen as a murder weapon if they were familiar with its properties? Which means that the murderer is probably someone who is used to handling liquid nitrogen on a regular basis.”

  “That doesn’t narrow the field hugely, I’m afraid,” said Seth. “Liquid nitrogen is used in all sorts of places these days—really, you don’t have to be much of a specialist to encounter it. It’s used as a coolant in superconductor systems, for example, and to shrink-weld machinery parts together. It’s even used in some fancy bars to create those smoking, bubbling drinks for novelty effect.”

  “Oh.” I sat back, disappointed.

  Seeing my expression, Seth said, “But it certainly wouldn’t hurt to check and see which of the suspects might have experience using liquid nitrogen.” He glanced down the table to where Devlin was sitting, then turned back to me and said, “Is the show going to be on hold much longer?”

  “I don’t know. I think the police are getting a lot of pressure from Monty Gibbs to reopen the concert hall and let them continue filming… and with the lack of new developments, Devlin may have no choice.”

  “Oh good,” said Seth, looking pleased. “Then we can watch the rest of the Semi-Finals performances.”

  I stared at him. “Seth! Don’t tell me you follow From Pleb to Celeb too?”

  “Well…” Seth looked down and fiddled with his fork, a line of colour on his cheeks. “I know it’s not very highbrow… but it is very good telly.”

  “Yes, I suppose… Do you vote as well?”

  “I haven’t yet. But Cassie and I were planning to vote in the Semi-Finals.” He gave me a grateful look. “Thanks for the tickets, by the way. It was fantastic getting to see the acts live, even if things got cut short. I hope they let that magician chap repeat his act—I was really enjoying it when it was interrupted. Did I tell you I used to be really into magic as a boy?”

  “Really? You mean you wanted to become a magician?”

  “Well… I did have an amateur magic set, but what really interested me was the evolution of magic as a performing art. You know it’s one of the oldest performing arts in the world? During the eighteenth and nineteenth centuries, large magic shows in big theatre venues were really popular, and illusionists were treated like great stars. I used to spend hours reading up on the different magicians and their individual styles, and learning all the different categories of magic tricks.”

  I rolled my eyes and laughed. “Seth! Trust you to turn a fun hobby into a geeky obsession.”

  “It wasn’t an obsession,” said Seth indignantly. “I just liked to find out how the tricks are done. From an academic point of view. It gives great insight into the human capacity for misdirection and self-delusion, you know. Like the ‘Zig-Zag Girl’ trick, for example, when the magician divides his assistant into thirds—and she’s still smiling and waving at you from each section—and then he ‘rejoins’ the pieces and she emerges from the box completely unharmed.”

  “Yeah, I’ve seen that—I just don’t understand how they do that!”

  Seth laughed. “It’s all about having the right props. It’s actually fairly easy—the assistant just has to contort her body in a particular way, inside the specially constructed box. It’s the same with the chair trick that Albert does at the end of his act—you know, when he covers himself in a sheet and sits in a chair… but then he suddenly reappears on the other side of the stage… I’ll bet that chair has a seat with a false bottom which opens—”

  The sound of a fork being struck against a glass made everyone stop talking and look up. The president of the society stood facing the room with a welcoming smile. He made a little speech, then introduced Devlin and invited him to the podium. The room fell silent, everyone’s attention rapt as Devlin gave a fascinating talk on why people were driven to murder, the different types of motivations, and the range of reactions to the aftermath of the deed, from those who immediately confessed in a fit of guilt and remorse, to those who would happily murder more people to cover up their crime.

  As I listened, I couldn’t help thinking of Lara’s death and the potential suspects in the case. What was the reason for this murder? Was it greed and gain? Bitterness and revenge? Fear and self-defence? Or just plain insanity?

  CHAPTER TWELVE

  Although we didn’t leave Montague College until well after ten o’clock, Devlin followed up on his promise and took me to the Quod Restaurant & Bar for late-night drinks. The bar was part of the Old Bank Hotel, lo
cated in prime position on the High Street, sandwiched between some of Oxford’s oldest colleges, and facing St Mary’s Church and the iconic buildings of the Bodleian Library. The hotel also had special meaning for me because it used to be my father’s bank—in fact, it had been the main Oxford branch of Barclay’s Bank for over two hundred years, before the building had been bought by a millionaire art collector and turned into a boutique hotel. I could remember my father taking me with him when he’d gone in to do his banking there. Now, the beautiful fourteenth-century building—with its Georgian alcoves, wood-panelled walls, and large sash windows—played host to tourists, businessmen, and other visitors to Oxford, and revelled in its status as the only hotel right in the heart of the university city.

  Despite the late hour, the restaurant was still humming and we were lucky to find two empty stools at the white onyx-topped bar that dominated the room. Devlin glanced at the bar menu, then handed it to me and said with a grin:

  “I bet I know what you’re having—the Rose & Rhubarb Bellini.”

  “Oooh, that does sound nice…” I perused the menu myself, then gave him a teasing look. “And I suppose you’re having the Basil Daiquiri?”

  Devlin pulled a face. “Not unless someone gives me a lobotomy! No, it’s a pint of beer for me. I’m having the Cotswold Premium Lager. What about snacks—do you want something to nibble with the drinks?”

  “Good grief, no…” I said, clutching my stomach. “That sticky toffee pudding they served at Montague College for dessert just about finished me off.” I looked down at the menu again and added wistfully, “Shame, as some of these sound very interesting… hmm… ‘Cornish brown crab on toast’… and what on earth is ‘black radishes with celery salt’?” I gave him a bright smile. “I know! We can come here to have a celebratory dinner when the case is closed.”

  Devlin raised his eyebrows. “You’re very optimistic. You do know that a large percentage of murder investigations never get solved?”

  “Yes, but I have complete faith in your abilities,” I said with a smile.

  He chuckled and leaned close for a kiss, but at that moment I happened to glance up and my eyes met the gaze of a man rising from a table near us. His face brightened as he recognised me and he hurried over, followed by his dinner companion.

  “Gemma, how nice to see you!”

  Devlin straightened, a look of chagrin on his face, but he turned and gave the newcomers a perfunctory smile. I looked warmly at the tall, good-looking man with the humorous brown eyes and open, pleasant smile. I had known Lincoln Green most of my life: his mother, Helen Green, was my mother’s closest friend, and in fact, the two mothers had always (and not so secretly) hoped that Lincoln and I would end up together. With his upper-middle-class background, Cambridge education, and impeccable “English gentleman” manners—not to mention being a doctor to boot—Lincoln was considered the perfect match.

  He was also a genuinely nice guy and I found his company very enjoyable. In fact, if I was honest with myself, I had to admit that if I hadn’t met Devlin again after all these years, things might have been very different between Lincoln and me. As it was, we were good friends, although sometimes I couldn’t help feeling that Lincoln still harboured a hope that we might become more than that. Devlin certainly seemed to think so and had always remained tense in Lincoln’s presence. It hadn’t helped that my mother had struggled to accept Devlin, with his working-class roots and unconventional upbringing, and—for a long time, I’m ashamed to admit—I had let her disapproval affect my own attitude too.

  Still, that’s all in the past now, I thought with an inward smile of relief. Since Devlin had demonstrated his technological sleuthing prowess (that is, he’d found her beloved missing iPad), my mother had suddenly decided that my old college flame was the best thing since organic sourdough bread and had welcomed him into the family with open arms… while I had finally realised that I didn’t need my mother’s approval to be happy.

  “What a marvellous coincidence,” said Lincoln, beaming and leaning down to give me an affectionate peck on the cheek.

  Devlin stiffened slightly, but took Lincoln’s proffered hand equably enough. “Good to see you, Lincoln,” he said.

  “Yes, we haven’t seen you in quite a while,” I said.

  “It’s been ages!” said Lincoln. “In fact, I think the last time we saw each other was during that morning tea your mother hosted, when your mother—” he glanced at Devlin, “—came to visit.”

  Devlin winced slightly at the memory of that day and looked even more uncomfortable when Lincoln added enthusiastically, “Your mum is brilliant, Devlin! I hadn’t realised how young she is. She’s a very attractive woma—” Lincoln broke off and flushed as he seemed to recollect himself. Clearing his throat, he finished lamely, “Er… I hope she comes down to Oxford more often.”

  Devlin looked like he was struggling to unclench his jaw to say something polite and I stepped in hastily.

  “Um… so how’s work, Lincoln?”

  “Oh, it’s going well. In fact, it’s Research Week at the hospital and I’m chairing the panel of guest speakers.” Belatedly, he remembered his companion and turned apologetically towards her. “Forgive me—this is Dr Elsa Kruger. She’s come all the way from Melbourne. We’re collaborating together on a research project about septic shock.”

  The pretty blonde woman stepped forwards to shake hands, her eyes lingering on Devlin with interest.

  “You’re not a doctor, are you?” she asked him.

  Devlin smiled. “No, my oath involves arresting people, not curing them.”

  “Oh—you’re a policeman?”

  He inclined his head. “Detective. CID.”

  “Wow, I’ve never met a real-life detective,” she said, fluttering her eyelashes and looking up at him admiringly.

  I resisted the urge to roll my eyes.

  Devlin chuckled. “I wouldn’t get too excited—it’s not as glamorous as they make us look on screen.”

  “Oh, I don’t know about that,” Elsa purred. “You could give any of those sexy TV cops a run for their money.”

  Oh, for heaven’s sake… I didn’t know whether to be irritated or amused by her blatant flirting. And judging from his wicked grin, Devlin was enjoying my discomfiture. Pointedly turning my back to them, I said to Lincoln:

  “How’s Jo? I haven’t seen her in ages either.”

  “Jo? She’s great,” said Lincoln, smiling as he mentioned his pretty forensic pathologist colleague. “She’s gone on holiday with a friend. They’re visiting Finland and hoping to see the aurora borealis.”

  “Oh, I’m so jealous! I’ve always wanted to see the Northern Lights. Although… it’s a cold time of the year to go, isn’t it?”

  “Well, you have to go between September and March for the best chance to see the lights, but I agree with you—it’s mid-winter now and a really brutal time of year. I can’t imagine how cold it must be up in the Arctic. Jo and her friend are probably freezing to death!” He realised what he’d just said and winced. “Sorry! That was a bit tasteless, given your experiences with the recent murder—”

  “It’s okay,” I said. “It’s been a few days and I’m getting used to it now. I think part of it was that it was so bizarre… almost unreal, in a way. I don’t know why but I think I would have coped with it better if it had been a stabbing or something.”

  “That’s understandable,” said Lincoln. “We deal better with things that we can make sense of. It’s probably why early man developed so many myths and superstitions—it helped us cope with natural phenomena which puzzle us. You know, many people believe that the legend of the werewolf originated from medical conditions such as porphyria, which causes reddish teeth and psychosis, or hypertrichosis, which causes excessive hair growth all over the body. Some even think it came from people’s fear of rabies. Of course, now we know the scientific bases behind all those conditions, but in medieval times it was probably comforting to blame the symptom
s on a ‘werewolf’ curse.” Lincoln gave a self-deprecating laugh. “Sorry… this is probably boring you.”

  “No, no, it’s really interesting. I can see what you’re saying. It makes me feel better, actually, for getting so freaked out.” I paused, then added thoughtfully, “You know, I thought having such an unusual murder weapon would make it easier to catch the killer, but Seth told me that liquid nitrogen is used in lots of industries and it’s actually pretty accessible. Apparently, they even use it to make fancy cocktail drinks!” I glanced across the counter at the bartender, wondering if they used it here.

  “Yes, you do encounter liquid nitrogen in a lot of places. We use it a fair bit in medicine—to preserve tissue samples and biological cells, and also in cryosurgery to burn off warts.”

  “But you’d have to be a scientist or medical personnel to get hold of it, right?”

  “No, I believe you can order it easily on the internet.” At my incredulous look, Lincoln added, “The thing is, in the overall scheme of things, liquid nitrogen isn’t considered that dangerous. If it’s handled correctly and with respect, it’s a very useful element to have. There are far more dangerous, reactive substances that are found in every household, such as products made from chlorine.”

  The barman came over for our orders, interrupting the conversation, and Lincoln gave Devlin an apologetic look.

  “We’d better head off and leave Devlin and Gemma to their drink,” he said, putting a hand under Elsa’s elbow.

  The blonde woman pouted. “Oh, we don’t have to go yet, surely? I’m sure they wouldn’t mind if we joined them for a bit.”

  I do mind very much, especially if you’re going to keep leaning into my boyfriend like that, I thought sourly, watching her. Any closer and you might as well climb into his lap!

  To my great relief, Lincoln said: “Don’t forget, Elsa, you’re speaking at the breakfast symposium tomorrow morning and that starts at seven-thirty. So we’d better get an early night.” He turned to me, saying with a smile, “I hope we’ll catch up again soon, Gemma,” and held a hand out to Devlin.