When we left the block on Flicker Street, we emerged in hot air and dazzling sunshine and walked to the nearest tram stop.

"We need to go back to the university and talk to Jude," I said. "He has a motive for Lonn's murder -- and he could have killed Frankie, too. Maybe they both planned for revenge but fell out afterwards. Maybe it was just Jude's idea, and then she realised it was him and called him out on it. Or maybe he was just feeling possessive."

"That's a lot of maybes," Alex said. "What about Janet? If Frankie's errand was to confront someone, it could have been her. And she is living right next to the crime scene."

"It's possible," I conceded. "But let's deal with Jude first. How are you feeling now?"

"A little better," he said, although he looked just the same.

"Do you think you'll be up to that meal later? Maybe you should just rest."

He smiled, one side of his lips rising a fraction higher than the other. "For a moment, I thought you were concerned about me."

"I am!"

"You're looking for an excuse not to meet my parents."

"Maybe." I picked at a loose thread on my jeans. "I'm nervous."

"I know you are. That's good."

"It doesn't feel good." I looked up and raised my eyebrows.

"It means you care. They'll sense that, and they'll like you."

We entered Socrico University's campus, and a gaggle of students in miniskirts passed between us. I dropped the subject.

We went to Reception again and requested Jude Bray's timetable. A quick glance over it told us that he'd been released from his morning lecture, so he could have been anywhere. But he was due in a practical soon. We'd catch him then.

"While we're waiting," I said, "we should find Nora Fitzroy again. If Janet's to be believed, she knew Frankie better than the Temples. She might be able to tell us something useful. And, anyway, I'd like to check on her after she overheard the bad news."

We found the research building and took the stairs to Lab S. The door was still propped open, so I poked my head inside. Everyone was working, goggles clipped over their eyes.

I frowned and looked them over again. No. Everyone but Nora was working.

Riannon Sotello glanced up. Her lip curled. "If you're looking for the boss, she's slacking off in the cafeteria. She went down there for a glass of water when you left, and she still hasn't come back."

Everyone froze at their workstations. The tension in the air was so thick that even a train would have struggled to pass through it.

"Have you checked on her?" I asked.

"Why would I do that?" Riannon's eyes flashed. "I worked my arse off for Lonn, doing twice as much as her, but she gets his fucking job in the end. She can't even handle it! I'm running this lab. I'm doing all the extra work without the extra pay, while she sits down there and has, like, a fucking drink. I'm not playing nurse, too!"

"I think it would serve you well to remember that Nora has just recovered from breast cancer," I snapped, "and that she's lost two friends in the past week. She needs your support, not your criticism."

Riannon folded her arms. "Why do you care?"

"I care because I don't like your attitude. It's uncalled for. In any case, I've decided that I'd also like to speak to you."

"I'm too busy."

I stepped aside and gestured with my hand. "Get out here and answer my questions before I arrest you for perverting the course of justice."

She skulked out the door and slammed it behind her. "That's not very professional."

I cooled my tone. "Bitching about your boss to the rest of the room isn't professional either. Frankie Jarsdel was found an hour ago with her neck snapped like a twig. She was just nineteen. Some sensitivity about the incident would be appreciated."

Alex glanced down and cleared his throat. "How well did you know Frankie Jarsdel?"

"Not at all," Riannon said curtly. "That's dear Nora's territory. She was always the family friend Lonn looked on fondly. Meanwhile, I was just another minion."

"Did Frankie ever pop into the lab to see him?" I asked.

"No one's supposed to stick their nose in without permission, and no one really bothers. I don't even know what Frankie looks like."

"Did Lonn ever talk to you about her?" Alex asked.

"I just told you, didn't I? I was staff to him, nothing more. We were friendly as co-workers, but we weren't friends." She backed off and raised a cocky, oddly-shaped eyebrow. "Can I go now?"

"Where were you between five and seven yesterday?" I raised my voice as the distance between us grew.

"At home. And you won't find anything wrong with that alibi this time."

***

The staff cafeteria was based on the ground floor, at the end of the lobby. It was a bright, double-height room filled with enough glass tables to seat a few hundred people, but only a handful were there. I picked out Nora immediately, sitting near the automatic doors with her head down and her shoulders hunched.

We dropped onto the bench opposite her, and she looked up with red-rimmed eyes. Her expression slackened when they fixed on us. "Oh. Inspector, Sergeant."

"Hello," I said softly. "We're sorry for your loss."

She'd taken her lab coat off, and now she rooted around in the pocket of her trousers for a tissue. Her short hair fell over her eyes. "Thank you. This has all been so sudden. First Lonn...now Frankie."

"We need to talk about Frankie," I said. "We've come to understand that you were close to her. Closer than Lonn and Janet."

"I suppose. I only met her last year when her mother died and she went to stay at Lonn's flat. We always got along. Lonn did once confide that he thought she was only herself when I was there."

"So would you say that you and Frankie were close?"

"Well, I only saw her occasionally when I was invited to dine with them." Nora swallowed thickly. "But she was always a pleasure to talk to, and I'll miss her."

"Did you ever discuss personal matters?"

"No. Just our enthusiasm for biochemistry."

"So you don't know if she had any enemies?" I was beginning to feel like a broken tabphone voice recorder.

"No. I don't know anyone she associated with apart from myself, Janet, and Lonn." She braced her elbows on the table and let her head fall into her hands. "Poor Janet. She never asked for any of this."

"Frankie told one of her flatmates that she was going to run an errand yesterday afternoon. Do you know what the errand might have been?"

Nora kept her head down for a long moment, seeming to collect herself. At last, she raised it. "No."

I sighed. "I'm sorry. I know our questions aren't helping, but I just have to ask one more thing. Where were you between five and seven yesterday evening?"

"At home with Petr."

"Okay. Thank you, Nora." I stood up. "We'll leave you in peace now."

***

A while later, we found ourselves standing outside a student lab. Dozens of them were squashed inside a towering building that looked older than Socrico itself. The archaic effect was ruined by the overpowering stink of methane and burned gauzes.

While I peered through the door at the lab tables arranged in rows, Alex leaned against the wall beside me. "Not even Nora has an insight into Frankie's mind. Maybe we came the closest."

I glanced back at him. He was wearing the distant look I knew too well.

"Hey, this reminds me of secondary school." I tapped the plastic window in the door. "Our labs smelled like this, and they looked almost exactly like it, too."

"Was science a good subject for you?"

"It depended on what we were doing. I loved biology. Chemistry was okay, although I did once set fire to my blazer." I smiled fondly. It had been embarrassing at first -- and my family had all been horrified when I'd got home -- but I'd worn that charred blazer for the rest of the school year and felt kind of cool about it. "Physics was the worst. Trying to put electronic circuits together or even understand how they worked was always a disaster."

Alex almost smiled. "I'm not surprised."

The double doors at the other end of the corridor flew open, and a group of students poured in. Those who'd already been waiting in the corridor straightened up, Alex included, and we all craned our heads to focus on the new arrivals.

I spotted Jude first, among the fourth wave of arrivals. I tapped my sergeant's arm to warn him, and we moved into the middle of the corridor.

Two immobile people in the racing sea caught Jude's attention immediately. His eyes narrowed, but his stride didn't slow.

"Becky told me," he said as he passed. His eyes were red. "And I don't want to talk about it."

"Too bad." I turned on my heel and followed him to the end of the line he'd joined. "We do."

He scowled. "My friend has just died, and I have a practical in zero minutes."

"I don't care. We can do this the easy way or the hard way, but we've heard a lot of bad things about you. We're not walking away."

"The hard way?" Jude's scowl turned into a strange smile. "Are you suggesting you'll take me outside and beat me up, Inspector? I think that's against the law."

I raised my voice. "The hard way is that I arrest you for common assault."

The chatter in the corridor quietened. Jude's mask of charm slipped again as heads turned his way. He glowered. "Fine. I'll talk for five minutes. Outside."

I nodded at Alex, and he hung back to bring up the rear while I led the way out. Curious gazes followed us.

Once we were outside, I slammed on the brakes and turned to face Jude, gravel flying beneath my boots. "Where were you between five and seven yesterday evening?"

He shrugged, coming to a slower stop. "I don't remember. In my dorm, probably."

Alex fixed the boy with a cool stare. "We need more than probably."

"Let's try again," I said. "Frankie died between five and seven yesterday evening. Where were you?"

"In my dorm!"

"And your flatmates will confirm that?" Alex asked.

Jude looked away. "Maybe."

"What about Thursday night, between seven and nine?" I said. "You told us you'd been at a friend's party. Whose?"

Jude shrugged. "I don't remember his name."

"How stupid do you think I am? Tell us."

"No."

"Okay. Then let's go back to the Friday night before that - Friday, 26th May. You went to a club with Frankie and Becky. Which one?"

"I don't remember." He wouldn't even look at me.

"Underworld Eclipse, I'm guessing. You all got drunk. Filled with Dutch courage, Becky kissed Frankie. You weren't too happy about that -- you wanted Frankie for yourself. So you had an argument with Becky, you cornered her, and you made out that you were going to hit her."

"Fucking tattler," he spat. "I didn't hit her."

"It doesn't matter. You made her think you were going to, and that's assault." I paused to let that sink into his stubborn brain. "Jude, I'd like you to come with us to the station. Voluntarily."

He finally met my eyes again. "And if I say no?"

"I'll arrest you for assault." I pulled my handcuffs halfway out of my pocket. "While you're getting comfortable in the custody suite, I might just charge you with murder as well."

***

Once we'd got Jude to the police station, we left him in an interview room for a few minutes to get coffee and regroup. When we came back, we watched him through the mirrored glass. He was slumped in his chair, his expression a gritty mixture of self-blame and sorrow.

We pushed the door open and sat down opposite him. I slid two printed pictures across the table: the overturned desk in Lonn Temple's office, and a close-up of the purple folder and papers scattered near Frankie Jarsdel's left hand in the lift shaft.

"This interview is being video-recorded," I said. "We are in an interview room at Socrico Police Station on 5th June 2186. The time is 14:00. I am Detective Inspector Amber Rames. The other police officer present is Detective Sergeant Alex Sullivan. Please state your full name and date of birth."

"Jude Bray," the student grunted. "3rd January 2167."

"Jude, I will remind you of your right to legal representation. I will also remind you that you are not under arrest and may leave at any time." That last part hurt to say, but I knew it would be difficult to get his common assault charge to stick in court. And I felt that I was on the cusp of something much greater.

"On Thursday, 1st June," I continued, "between seven and nine in the evening, Lonn Temple was stabbed to death inside his office at Lab S, Socrico University Research. On Sunday, 4th June, between five and seven in the evening, Frankie Jarsdel fell down a lift shaft on Flicker Street and suffered a mortal break to her neck."

"Is this some kind of accusation?" Jude asked.

"I'm stating the facts of our murder inquiry."

"Because you think I did it." He scoffed, but his jaw tightened. "You're wrong. She must have jumped. She could never fucking get over Paris, and your interference yesterday was the final straw."

"Was she suicidal?" Alex asked.

Jude spread his hands. "I don't know! After that thing at the club, I didn't speak with her again until Friday when we all heard about Lonn. She shut me out."

"Yes, let's talk about the incident at the club," I said. "You reacted strongly when Becky kissed Frankie. Becky says she's since realised you've had feelings for Frankie for a very long time."

"Before she was even with Paris." His whole body turned rigid. "I loved her."

"But you were angry with her for dating Paris. Then you were angry with her for holding on to his memory after he'd gone. Then you were angry when she was kissed by Becky."

He shrugged. "Maybe."

"A lot of murderers hold the view that if they can't have their victim's love, no one else should have it, either."

"You are accusing me!"

"We're telling you how bad things look," Alex said. "So now would be a good time to tell us where you were yesterday evening."

"In my room!"

"We will check with your flatmates," I said.

"Go ahead! I'm telling the truth."

"Are you going to tell the truth about your other alibi this time?" I leaned forward. "What is the name of the friend whose party you attended on Thursday night?"

Jude's gaze slid away. "No comment."

"Fine, we'll just move on to another topic...like your motive for Lonn Temple's murder."

He looked up. "I barely even knew the guy."

"But I bet you knew the puzzle pieces. Lonn Temple murdered Paris. Lulu Jarsdel wrote about it in her diary. Frankie found the diary when she died. You were Paris' best friend -- and Frankie's friend, too. So did she tell you, Jude? Did she tell you what was in the diary?"

His eyelids fell over his pupils like a shutter. "No. She showed me."

"Did she show it to anyone else?" Alex asked.

"Just me. She thought I should know the truth."

"So," I said, "let's imagine this: on Thursday evening, you entered Lab S, struggled with Lonn Temple, and proceeded to stab him to avenge Paris. But the murder of Lonn and the discovery of Paris made Frankie think deeply about her mother's diary, and after she left the police station on Sunday, she came to a conclusion. She thought that you'd killed Lonn, and she confronted you about it. You pushed her down the lift shaft to silence her. Does that sound right?"

"No!" Jude's ferocious gaze clashed with mine.

"Then tell us who you were with on Thursday night and what you were doing!"

He slammed his hands down on the table. "Fine! I was at a flat party -- Colton Drake's. We all got smashed, and I crashed in his dorm for the night. I was there until about nine the next morning."

"What time did you get there?"

"Seven. And I swear I was there all night."

He looked down again. I watched him closely, letting an awkward silence settle over the room. There was something he still wasn't telling us.

Think. What happened at that party? What might a nineteen-year-old do that he wouldn't want a police officer to know about?

At last, he looked up. "Er...Inspector? Are we done now, or...?"

I shoved my chair back and stood. He jumped a mile, but I ignored him and turned to Alex. "Jude wasn't searched when we brought him into the custody suite, was he? Because we haven't arrested him."

Alex looked bemused. "That's right."

I turned back to our interviewee. "How do you feel about being searched, Jude?"

He leapt to his feet. "You can't do that!"

My gaze fell to his pocket. He'd done exactly what I'd been expecting -- shoved his hand inside on instinct. His knuckles were pressed against the denim as he clutched something in subconscious panic.

"Why don't you empty that?" I asked.

He froze.

"I have reasonable suspicion to believe you're carrying an illegal substance," I said. "I can have you searched without your consent now. Just make it easier for both of us."

He slowly drew his hand out of his pocket. Cradled in his palm was a small packet of blood-red powder.

I raised my eyebrows. "Crimson. Is that what you were taking on Thursday night?"

He just stared at me. He knew he was buggered.

"Jude Bray," I said, "I am arresting you for possession of a Class A drug. You do not have to say anything, but it may harm your defence if you do not mention, when questioned, something which you later rely on in court. Anything you do say may be given in evidence."