McEvoy stared out of the window, ignoring the reports in front of him. It was going to start raining again shortly. The sky had darkened from the west and a breeze was picking up signalling a new front arriving. He wanted to head off to the canteen but was worried about how he'd be received, who he might bump into on the corridor.

He needed to find something else to do, something that would keep him out of the building, but off the street. The only things he could think of was re-visiting Donabate beach or taking the rest of the day off ill. As he puffed on his plastic cigarette his mobile phone rang.

'McEvoy.'

'It's John Joyce. We've got a witness,' he said excitedly. 'A young woman who recognised Laura and saw her talking to someone she knows. She's waiting for us at Drumcondra Station. I'm on my way there now.'

'She say who it was?' McEvoy asked, anticipation building inside of him.

'One of her lecturers. She's a student out at Maynooth University. I don't have a name yet. I'll ring you as soon as I get there.'

'Don't bother, I'm on my way. I'll see you in five minutes.' He started to run for his car.

A Citroen was parked up on the pavement under the railway bridge that crossed Drumcondra Road. Dr John was sat in the driver's seat, a young woman on the passenger side. A few feet away, near to the train station entrance, a guard was chatting to one of the woman's friends. McEvoy opened the back door and climbed in.

'So?' he asked.

'This is Aoife Ni Chaireallain,' Dr John said, turning in his seat, 'she's studying Irish and politics in Maynooth. This is Detective Superintendent Colm McEvoy.'

'Hi,' she said quietly, looking back at him, apprehension in her eyes. She looked no more than 18 or 19 with long, dyed blonde hair pulled into a pony tail, a pale oval face, dabs of foundation cream covering a couple of spots on her chin and cheeks.

'Hi, Aoife. DS Joyce tells me you recognise the girl in the photos and also saw her with someone you know?'

She nodded. 'I used to see her sometimes, y'know, just wandering about or sitting on steps, like. She looked kind of lonely, y'know. I felt bad for her, but, well ...' she trailed off.

'There's nothing you could have done, Aoife. She didn't want any help. Who did you see her talking to?'

'It was one of my lecturers, Dr Andrew McCormack. At least I think it was him. He was wearing a baseball cap, but I thought it was him.'

'How positive are you that it was Dr McCormack?' McEvoy asked, his heart pounding in his chest, wanting to leave the car and raise the alert.

'I ... I don't know,' she replied hesitantly, 'I mean, I thought it was him, y'know. I was on the other side of the street, so, I don't know. I see him round there all the time.'

'Round where?'

'Phibsborough Road.'

'How come you never came forward with this information before?' McEvoy said, thinking that Phibsborough Road was only a stone's throw away from the Mater Hospital.

'I didn't ... I don't really watch the news or read the papers, y'know. It's the first time I've seen her pictures, y'know, really seen them. I didn't think ...' she tailed off. 'I didn't recognise her in three of the photos,' she tried to explain, 'just one of them. Am I in trouble?'

'No, no,' McEvoy tried to reassure, shaking his head at her ostrich-like approach to life.

'Anything grizzly I switch channel,' she continued to reason, 'it gives me nightmares. I know that bad stuff happens, I just don't want to see it, y'know what I mean? If I don't see it, like, I don't have to think about it. She's one of the murder victim's isn't she? The Raven or whatever he's called?'

'Yes. She was the first victim.'

'And Dr McCormack's The Raven?' she said, the connection finally clunking into place.

'We don't know yet,' McEvoy said evenly. 'That's something we're going to have to check out. While we do that we're going to need you to be formally interviewed and to make a full witness statement. It should only take a couple of hours.'

'But what about university?' she asked absently.

'It'll still be there this afternoon or tomorrow. How about your friend? Does she know who you thought you saw Laura with?'

'She was there when I told the guard.'

'Okay, well she'll have to come with you as well then. You haven't made any phone calls or spoken to anyone about this, have you?'

'No. Only to you and the guard over there.'

'Good, because I don't want this information circulated. It's to be kept between us until we've spoken to Dr McCormack. If he is The Raven, and there's nothing to say he is, I don't want him to run away before we've had a chance to talk to him. If he does get away, he'll kill again. I've no doubt about that.'

'I, er, yes, okay,' she stuttered. What colour there was in her face had drained away.

'Good. You've done the right thing talking to us, Aoife. I'll just get your friend. If you want, ring your parents, let them know where you are, but do not say anything about Dr McCormack. Can you explain all that to her friend?' he said to Dr John.

'Yeah, no bother.'

McEvoy stepped out of the car, a new energy coursing through him. This was the lead they'd been waiting for, he was sure of it. There had been little reason for McCormack to have surfaced as suspect. After all, he was writing a book on how to commit the perfect murder. If he had been following all of his rules, then he would not have cropped up at all. The victims would have been random selections who simply vanished, their bodies never discovered. He called up Roche's number.

'Colm, I'm in a meeting, is this urgent?'

'We have a name. Dr Andrew McCormack from Maynooth University. We have a witness who saw him talking to Laura Schmidt. He's based in the same department that David Hennessey worked in.'

'Jesus!'

'My gut says it's him, Paul. It all fits together. He knew Brady through Hennessey.'

'You'd better get back here, pronto. We need to do this properly; the last thing we need is for him to slip away again. I'll talk to Bishop.'

'You'll be better off keeping him out of this.'

'I agree, but we haven't a choice.'

'I'll be back there in ten minutes. We need to find out if he's come up before in the investigation.'

'I'll get Padraig O'Keeffe on it now. I'll also see if he's got previous form. I'll see you shortly.'

McEvoy ran to the station door, his oversized suit jacket flapping, and took the steps inside two at a time. He arrived at the incident room half out of breath, gulping down air. The room was a hive of activity but Paul Roche looked up when he entered and started to cross the floor to him.

'Let's find somewhere quiet,' Roche said, re-opening the door, letting McEvoy pass through. 'He's no previous form. He was interviewed by Charlie Deegan the day after Hennessey's murder.'

'I should have known,' McEvoy muttered, trailing after Roche. 'For feck's sake!'

'It gets worse. His interview notes were the absolute minimum. According to Simon Grainger he only bothers to write them up in full if he thinks it's going to be worth the effort. In other words, he only does it if he thinks the person's a suspect.'

'So we've no interview notes!' McEvoy said exasperated.

'No, but before you blow your lid, I've spoken to Deegan to see if he remembers him. He said McCormack was a pretentious prick, which is nicer than what he said about you. He said, he was flippant, arrogant, and up his own arse. A typical academic as far as he was concerned.'

'You sure he wasn't looking in a mirror?'

'His description seems to match Kathy Jacobs' profile,' Roche continued, ignoring McEvoy's bile.

'We could have nailed this bastard earlier in the week and saved the lives of several people. Feckin' Deegan. Unbelievable.'

'Maybe, maybe not,' Roche replied, wistfully. 'We've interviewed hundreds of people in the last few days, Colm. Who knows how many of them have told us a bunch of lies? Probably a couple of dozen and not all of them can be The Raven. It might have taken us months to work through them all, double checking them.'

McEvoy stayed silent and scratched at his head, fuming inside.

'And it might not be him. Just because he knows David Hennessey and he might have been seen with Laura Schmidt does not mean he committed the murders.'

'He committed them!' McEvoy snapped. 'We both know he did. He's been leading us on a merry dance all week. He must be grinning like a Cheshire cat. He knows the investigation's barely touched him. He probably thinks he's home free.'

'If he'd followed all of his rules, he would be,' Roche said sighing. 'And even if it was him, he's probably got a bunch of cast iron alibis.'

'Forensics,' McEvoy stated. 'We have the matching hairs from Glencree and Rathmoylan.'

There was a knock at the door.

'Yes?' Roche said loudly.

Simon Grainger pushed it open, looking slightly ashamed, and handed a couple of sheets of paper to Roche. 'A bit of background information on him from his website,' he said before exiting.

Roche read out selected highlights. 'Undergraduate degree from Trinity in politics and sociology, masters in political science from Berkeley, and PhD from Harvard on the Politics of the Welfare State in Ireland, 1922-1992. He then worked as a postdoctoral research fellow at Cambridge University before taking up the lectureship in politics at the National University of Ireland, Maynooth, a couple of years ago. Specialises in the political science of the welfare state and the Catholic Church and the political system in Ireland. He's authored one book, edited two others and has published a bunch of articles. You want a look?' He held out the sheets.

McEvoy took them and studied McCormack's photo. He looked remarkably normal in his early to mid thirties wearing a Red Sox cap and smiling into the camera. There was no hint of any danger or malice, nothing to suggest he might commit a series of heinous crimes. McEvoy scanned down his potted academic history. 'How do you want to do this?' he asked, keen to get on with things.

'Chances are he's either fled or he's at work or home. We send teams to both of them and do a simultaneous raid. Inner and outer cordons at both. If he's not there, then God knows where he is and I think we just put out a nationwide appeal for help.'

'You don't want to wait until he shows back up again?'

'If he's gone, he's probably long gone, and we're not going to be able to sit on the name for very long. There's a good chance that one of our lot has already leaked it for a nice fee from one of the papers or TV stations. Once it's out it'll spread like wildfire. The best thing to do will be to release his name and photo and start a manhunt.'

McEvoy nodded in agreement.

'I'll take his house he lives in Lucan you take the university,' Roche instructed. 'Put people at all the exits and then go to his department. Make sure you've got plenty of backup, but when you go in act decisively, we don't want him to take a hostage or kill himself. I want this to end cleanly and to go to trial.'

It had started to drizzle again as they passed through the main gates to Maynooth University. McEvoy parked the car under a large chestnut tree next to the wooden hut just inside the gates.

'I'll be back in a minute,' he said to Barney Plunkett and Kathy Jacobs exiting the car, the confidence of an hour ago having started to drain away, his mind tumbling over the rationale of his initial certainty, trying to decide whether he was guilty of grasping at a nettle too quickly and firmly.

Martin Cleary and Tom Meaney were waiting for him in the hut, the heat turned up high, designed to take the chill and damp off bodies that had been walking around the campus grounds.

'Martin, Tom, thanks for meeting me,' McEvoy said, extending a hand, feeling awkward.

'So what's this about, Colm?' Cleary asked with a hint of a smile.

'We think we might have identified The Raven. We have a witness who's positively ID'd him. He's a lecturer in the university. He's been interviewed before, so we're going to take the softly, softly approach initially. Routine investigation. We'll do it while classes are on so there are less people around.'

'Who is it?' Cleary asked. 'Let me guess, someone from Hennessey's department?'

'How'd you know that?' McEvoy asked suspiciously, wiping at his nose.

'Come on, Colm, if I told you it was someone at the university that killed Hennessey, where would you start? With people who knew him well. I'm beginning to wonder if they might have been desperate to give you my old job.' It was said as a joke, but it came out flat.

'Maybe they were,' McEvoy said, taking the comment at face value. 'Jesus. We've ballsed this up from the start. The lecturer's name is Dr Andrew McCormack. That ring any bells?'

'Young chap, sideburns, bit abrasive, but friendly enough,' Cleary said. 'I wouldn't have him pegged for the murders, but then again most murderers appear relatively normal until you scratch away at the surface.'

'What do you want us to do?' Meaney asked.

'Nothing. I just wanted to let you know what's happening. This might be a wild goose chase or it might be the end game. Hopefully, it will go smoothly, but if it doesn't then we'll probably need your help.'

'I'm coming with you to the arts building,' Cleary stated. 'I know this place like the back of my hand. And I know the staff in there; it'll just look like I'm showing you to his office.'

'I'm not sure that's a good idea,' McEvoy said.

'It wasn't a request, Colm. I'm not having a cock-up like O'Connell Street happening here while I'm on duty.'

They swapped anxious glances, then set off towards a long, single-storey building, climbing five steps, entering through a set of automatic doors into an open foyer, the doors to two lecture theatres in front of them. They veered to the right heading down a narrow corridor along which the politics department extended. Skipping the secretary's office they headed straight for McCormack's door, Cleary and Plunkett taking up positions either side.

McEvoy's chest felt as if it had been wrapped in barbed wire, slowly being tightened. He knocked twice and tried the handle. It was locked. He knocked again.

'Shit!' he hissed. 'He's not here.'

'He might be teaching,' Cleary said. 'The secretary will have a timetable, she'll be able to tell us where he is.' He looked at his watch. 'We should be able to get to him before he leaves the lecture theatre.'

They backtracked to the first office on the corridor.

McEvoy knocked and pushed the door open, feeling heavy limbed and light-headed, his heart pounding in his chest.

The woman at the desk looked over at him, a look of mild annoyance on her face. 'Yes?'

'Detective Superintendent Colm McEvoy.' He stepped into the room. 'I wonder if you could help me?'

'Is this about David? I still can't get over the fact that he's been murdered.' She looked like she was going to cry. 'Terrible. Absolutely terrible.'

'Actually, I was wondering if Andrew McCormack was in today? I wanted to follow up on something with him.'

He followed her gaze right, Martin Cleary having followed McEvoy in.

She looked back at him. 'Andrew? No. No, he's not. He's not in all week. He's at a conference in the US. Boston, I think.'

'In the US?' McEvoy repeated, feeling sick, his mind racing.

'Yes, he was flying there at the weekend. Some big political science conference. He goes every year. He won't be back until next Wednesday. Is it urgent?'