The confessionals at St Emydius, as in most Catholic churches, had three compartments – one in the middle for the priest, and one on either side of him for the repentants. This time the hesitation came from Father Gorman. Dooher heard him slide open the window on the other side, then close it. 'No, we're alone. You can begin.'

The old words, the ritual he so loved. Again he made the sign of the cross. 'Bless me, Father, for I have sinned.'

John Strout, San Francisco's coroner, was a gangly Southern gentleman of the old school. He had a prominent Adam's apple, a perennially bad case of dandruff in his wispy gray hair, poor taste in clothes, and a pronounced Dixie accent. He was also, rube or not, one the country's most respected forensics experts, and now he was taking a morning walk with Glitsky through the debris and detritus of south-of-Market San Francisco.

It was Monday morning – sunny, breezy, and cold. Strout was, of course, a medical doctor, and – after a lifetime of bad morning coffee and stale donuts – had recently been a convert to the theory that a healthy breakfast was the key to a long life and perhaps even more luxuriant hair growth. Like all good converts, he had found the truth and was going to spread the word around, goddamn it. Like it or not.

So, whenever feasible, he'd taken to briefing cops and DAs about his forensics reports over breakfast in one of the city's eateries. It never occurred to him that discussing the finer points of often-gory violent death, complete with color photographs, might not be particularly conducive to stimulating the early-morning appetite.

It did occur to Glitsky.

Strout had finished the PM on Victor Trang on the previous Friday afternoon, and Glitsky had – atypically, in Strout's experience, probably because of his troubles at home – said he'd be free to discuss the results first thing Monday morning. Let the weekend intervene. Why not?

'I'll just look at the pictures while we're walking here, if you don't mind, John.' With a show of reluctance, Strout handed over the folder, and put his now-empty hands into the pockets of his greatcoat against the chill. 'What do we have?' Abe went on. 'Any surprises?'

'Well, as a matter of fact…'

Glitsky closed the newly opened folder. 'What? I'll listen first.'

'Surprises may be too strong a word, but the deceased here got himself gutted by a pig sticker of the first order.'

'Pig sticker?'

'Knife.'

'A pig sticker is a certain kind of knife?'

Strout's expression betrayed a certain intolerance. 'Damn, you Yankees… pig sticker means knife. Genetically. Victor Trang got stabbed by a big knife, is that clearer? And not just any big knife, something like a Bowie or my own favorite guess, a bayonet. Y'all familiar with the term "bayonet"?'

Glitsky played along. 'I've heard of it. Made by the Swiss Army people, right? Whittling tool.'

'Yeah, that's it, 'cept the large version.' Strout put a hand on Glitsky's arm and stopped him as they walked. 'Open the file,' he said. The breeze gusted and they moved into the entrance of an office building, out of it. 'The photos.'

Glitsky followed instructions, flipping over glossies of the murder scene, the body as he'd found it, then as it looked from various angles stripped on the morgue table. Finally Strout put his finger on one. 'There you go. That one.'

It was a color close-up that Glitsky recognized all too soon: the wound itself, after the area had been washed – long and wider than most knife-wounds he'd been witness to.

'You see there?' Strout was saying. 'Right at the top?'

Glitsky squinted, not clear what he was supposed to be seeing. Strout moved in closer, put his finger on the area over the top of the gash. 'Right here. You see that half-moon? The little circle under it? Know what that is?'

Glitsky took a second, then guessed. 'It's an imprint from the haft of the knife.'

The coroner was pleased. 'I must say, it is a pure pleasure to work with a professional. That's exactly what it is. The perp stabbed him so hard and so far up, the haft left this little fingerprint, which is pretty damn distinctive, you ask me. Actually cut into the skin above the blade area. I wouldn't put my name on it as a definite,' – this was because he could never prove it for certain and some attorney might discredit his entire testimony if he wasn't one hundred percent positive and correct on every detail – 'but between us, this could be nothing but a bayonet.'

Strout reached inside his greatcoat and extracted a folded brown paper shopping bag. 'As a matter of fact…'

'You just happen to have one handy.'

This wasn't as unusual as it might have appeared. Strout's office contained an impressive collection of murder weapons from throughout the ages – maces, crossbows, garrotting scarves, sabers, handguns and Uzis. And, apparently, bayonets.

He withdrew it from the bag, hefted it affectionately, and handed it to Glitsky. 'I thought I'd cut my steak with this at breakfast. Make an impression on our waiter. But look.'

Abe was already looking. It was, as Strout had noted, a pig sticker of the first order. Where the blade met the handle of the knife was an oversized steel haft with a half-inch circular hole through the metal.

Strout was pointing again. 'That's where it connects to the mount of the rifle.' Then back to the picture. 'It's also why there's that kind of double circle – the top of the haft, then the punch-out area… couldn't really be any thing else.'

'How common are these things, you think?'

Strout shrugged. 'Well, they ain't exactly Carter's Pills, but anybody wants could get ahold of one. Army/Navy stores, gun clubs, mail order, good old paramilitary-type boys saving our country from the government… your guess is as good as mine. Round here they probably wouldn't be as common as, say, in Idaho or Oregon, but you'd find 'em.'

'Also, ex-Army,' Glitsky said. Suddenly, he experienced a small jolt of connection. Mark Dooher. Vietnam and his dead troops. He closed his eyes, trying to re-visualize the photograph he'd seen in the attorney's office, whether there might have been a bayonet mounted on any of the many weapons displayed. He couldn't see it, couldn't bring it back.

But Strout was going on. 'Actually, Abe, that might be a tougher nut. If memory serves, they take your weapons away when they muster you out. 'Course, you could smuggle 'em… people probably been known to.'

Rubbing his thumb over the bayonet's blade, Glitsky nodded. 'I don't think so,' he said. 'That would be illegal.'

After his Monday-morning breakfast meeting with John Strout, Glitsky had planned to get right on the Trang investigation – murders that didn't get solved in the first couple of days very often never did. But when he'd come back to the office, there had been another homicide. He had been on call last week, so normally this would have been someone else's problem, but this week's Inspector had called in sick and gone salmon fishing, and Glitsky appeared just as his Lieutenant, Frank Batiste, had despaired of finding an Inspector to assign.

Apparently, a fry cooker who'd been fired from a Tastee Burger in the lower Mission had returned to the scene of his humiliation and gone Postal – a new expression Glitsky loved. The ex-employee naturally killed none of the people with whom he had a gripe. He did, though, by mistake before he killed himself, end the life of a seventeen-year-old high-school student who'd stopped in for a hot chocolate. This new homicide brought Glitsky's workload to seven active cases, and put him inside and around the Tastee Burger for the rest of the day.

Now it was just before noon on Tuesday and finally he was at Mrs Trang's clean but cluttered apartment with Paul Thieu, his enthusiastic interpreter.