Of course, the darkest place of all is in a murderer's heart.

So they say.

The lifeblood that pumps around the body of a killer must be tainted. It must be a deeper shade of scarlet. Edging from deep red to black, night slipping into the liquid like a shadow drifting across the lawn as the sun sets beyond the horizon.

Would it be thicker than normal? Crawling rather than running through the veins and arteries? The evil of a murderer making it more viscous to match the viciousness of the deed?

No.

It isn't.

Blood is blood. Well, depending on which type of monkey you are, of course. Still, it's all blood. If you're a saint or a sinner, a monster or Mother Theresa, your own particular vintage of claret is much the same as the next person's. Granted, if you're dead, you'll be laying in a pool of it, as it seeps to the bottom of your body.

Well, if you're not walking around anymore, why should the blood? Not that it walks, exactly...

Jack laughed to himself. As a mortuary technician, his audience to these little jokes was less than lively. At least, he thought, he found himself funny. Sometimes he would have to stop what he was doing, hold the knife, as he made some mental quip or other that would set him off giggling.

It gained him a reputation as being a little odd. Laughing in the face of Death, whilst cutting open a cadaver, was frowned upon for some reason. But Jack would laugh at a funeral. In the most serious of situations, he couldn't help but have to suppress a snigger. It was his defence mechanism.

Well, it was nerves to be honest. The dead made him nervous.

One might think that a job in a mortuary might be an odd choice for such a man. One would be correct, but Jack had always thought himself to be somewhat left of centre. He was a loner, preferring the company of his thoughts to the chaotic ones of others. Thus he held the camaraderie of the deceased in high regard, however uneasy they might make him feel.

At least, though they didn't laugh at his jokes, neither did they deride his offbeat sense of humour.

He gave them names. Not necessarily the same ones as on the forms and wrist bands, but names anyway. He called them what he thought they looked like, believing they would have been that little touch lighter during life if only their name had matched their face. An Edward might have become a John. A Susan could be an Yvonne. They didn't seem to mind the change. They never complained, at any rate.

It had happened four years earlier. He'd only been a technician for a few months and was still getting used to being 'hands-in' with the cadavers.

He disliked the word. Cadaver sounded like the bodies were remnants, left over from a hyena's feasting. He preferred corpse. It at least gave some humanity to the person into whom he was placing his hands.

The body was that of a young man. He'd been brought in the night before. A crime had been committed, but Jack wasn't, as yet, a party to the particulars. He was there to photograph and to sample. He made the deep 'Y' incision and removed the ribcage, cutting it along the sides so that it would lift like the lid to a treasure chest, revealing the jewels hidden beneath.

He weighed and measured, and he made things ready for the pathologist.

Jack didn't aspire to that position. He didn't want the responsibility of giving causes or making choices and decisions. He was happy being the hand that helped. He enjoyed opening up the body to tell its tales and the closing of the curtains after the story was told.

The dead weren't his friends, but he felt welcomed by them.

He was fast, he was efficient and he was accurate. As such, he was left to his own devices much of the time in the knowledge that the way would be open for the real work to begin.

Four years. Time flies by when you're drinking rum, Jack's father used to say to him. Cirrhosis agreed and they went hand in hand to the great bottle in the sky.

It was late. The corpse had been waiting for a couple of days. The skin under the glaring lights was a vivid yellow, with the lower parts being purple where the blood had settled, chilling until such time as decomposition joined the party and they could putrefy together. The now familiar smell - cold meat, a metallic tang and antiseptic, bowels - did its best to defeat the Vapour Rub liberally applied to Jack's nostrils. It was a constant battle whose victor was never assured.

Brian was laid out on the body block. His head was back, the chest pushed forward. The photographs and samples from the extremities had been taken.

"I'm going in," Jack thought to himself. "I may be some time."

He laughed. Brian didn't.

The man was thick-set. He had a broad moustache that was sprawled across his top lip like a Lincolnshire Pork sausage that had been left for so long it had stumbled past mouldy and was now comfortably resting in hairy. Stubble sprouted across his chin and cheeks and his nose was a criss-cross of broken veins and pock marks.

His hands were immense and Jack could imagine them crushing anything that came close enough to be caught.

Brian, or Edward Corvak according to his wrist band, lay patiently for the first incision. Shoulders to sternum then down to pubis, kinking to the left of the navel. He didn't seem to mind either, being dead, when the ribs were cut for the removal of the chest plate.

Jack was still somewhat awed by this procedure. He felt as if he were gazing into Pandora's Box and all the evils of the world might spew forth. Secrets that should never be revealed could lie within the human form and Jack sometimes found himself talking to the corpse that he was eviscerating to calm it into not doing so whilst he was working.

Afterwards was fine. Unleash away, as long as he was elsewhere.

He was soon calmed, though, by the rainbow colours of the organs - an artist's tribute to the glory of nature.

The pericardial sac that housed the heart was waiting for him to knock on its door with his scalpel. Who was he to delay?

He first checked the pulmonary artery for a blood clot. It was clear, the walls a little thick, showing possible high blood pressure. At each stage, Jack spoke into his voice recorder, making copious notes. He was known, already, to be thorough and wanted to make sure he didn't miss anything. He felt it was better to record too much than too little.

The scalpel sliced into the pericardium easily, and Jack pulled it back to reveal the heart. From being a child, he had thought the human body - any body, in fact - to be a wonderful creation. Whether it was born of invention, evolution or accident, he didn't care, but he did have respect for its intricacies and its miracles. And at the heart of his wonderment was... the heart.

Without the heart to give the blood the kick up the corpuscle it needed to race through your veins your organs would pretty much suffocate. And you'd end up on the slab in Jack's hands.

His first thought was haemopericardium. A split in the aorta causing blood to surround the heart. The heart was black. Nothing wrong with that. It wasn't the first time Jack had seen hearts that appeared to be much darker than they should be.

But then there was a flicker. A shift. He looked up, thinking the lights had dimmed for a second. Someone had forgotten to put 50p in the electric meter, he murmured. The lights were steady. Their usual brilliance undiminished. He looked back down, blinking to help his eyes adjust.

Odd. The heart wasn't black anymore. It was its proper deep reddish-brown.

Oh well, Jack shrugged. On we go. Carefully but quickly, he removed the organs as one and laid them out for the pathologist to examine. Before long, he was finished and on his way home.

Edward Corvak. A lumbering brute. Hands that not only could crush, but did. It had started with animals. Small ones. He'd catch squirrels and mice. Squeeze them until they popped and crunched. As he grew, so did the size of his victims. Dogs. Cats. A sheep. If he couldn't hold the body, he was more than happy to squeeze the head. It took a little longer, and more force was required, but Corvak, one day to be called Brian, enjoyed a challenge.

He'd only killed three children before the blood clot reached his brain and the life he'd wrung out of so many others was snatched from him.

Jack woke sweating. The morning light streamed in through the wooden slats against his window, slicing his body into slivers of shadow. It took him a moment to realise he was shaking. It took another moment to realise why.

Jack didn't dream. Ever. Or rather, he didn't remember his dreams. Ever. He slept well and woke rested.

Must be that chicken he had last night. That'll be it.

A strong coffee and hot shower was enough to wash the nightmare from his mind and, by the time he was back at work, he'd forgotten it completely.

Until it came to putting the jigsaw that was Brian back together again. Then he couldn't help but look at the hands. He couldn't help but feel the weight of one, imagine it pressing down on his skull.

He shook his head and replaced the dead hand. It was a dream. Don't be daft. Get on with it.

Jack sighed, wiped his brow and proceeded to replace Edward Corvak's organs. Usually, he'd do his best, depending on the state of them post-examination, to rebuild the corpse to as close as nature intended as possible. It didn't really matter. Once the body was sewn back up nobody would know. Jack, however, had enough respect for both the deceased and for life itself, to honour the original design.

In the case of Corvak, Brian no longer, Jack just wanted the job done. The organs were returned to the cavity as they fitted, and if kidney shared personal space with lung then so be it. They'd have to learn to get along - at least until cremation quenched the fire of any argument they might have.

The dead made Jack uneasy. Edward Corvak, though he was no longer living and his innards (since being outards) were a jumble, scared him. He was relieved when the body was wheeled back into the freezer and he could move on to the next corpse.

Three months. Male. Jason/Phillip. A finger over 6 feet tall - or long, lying down. Incision, saw through the ribs, remove the plate, open the heart up.

Black. Like coal. Like shadows and space and the bit in the furthest corner under your bed, where you're sure there's a sock hiding but you just can't reach.

Jack gasped and Edward Corvak knocked on the door to his memory. Jack mentally locked the door, turning Corvak away and stared at the black lump before him. There was no potential flickering of lights, just a steady gaze in a brightly lit room.

The heart was black. Then it wasn't. Like a cover slipping from a bed, the blackness dissolved away, the heart returning quickly to red, though its edges were coated in yellowing fat.

Jack's heart fluttered in response, a hiccup in its rhythm.

No. A late night. An early morning. Tiredness and the beginnings of a headache. That was all. Dismiss, dismiss. Except it wasn't so easy this time. He could feel the memory of Corvak tip-toeing around his subconscious, but did his best to ignore him.

Get on, get on. Remove the organs. Lay them out. Clean. Weigh.

Jack did his best to avoid any thoughts of shadows on hearts or deceased murderers for the rest of the day and, that night, used vodka to wash away the remnants of the thoughts. It worked, vodka being a stronger warrior than his own psyche.

Until...

Jason. Or Phillip Tennison according to his birth certificate and his mother. A nice guy. Honest and polite and friendly. And then his wife died. A hit and run. Except he'd never had a wife. A few girlfriends now and then, but he was always too nice. Always too much of a friend to be a lover. What he did have was a chemical imbalance, precariously poised up to the point it slipped and fell and became a knife, slitting the throats of the raven-haired girls that resembled the non-existent wife who was so tragically torn from his side.

Jack wiped the sweat from his brow and the tears from his eyes. He waited for the shaking to subside and climbed out of bed, his legs unsteady as he turned the shower on full blast and full heat. In a daze, he was at work before he'd even realised he'd left his home.

What was going on? Why was he having these dreams? The dead had never affected him like this before. Why now? What was the deal with the hearts?

He thought of little more all day, the bodies before him being eviscerated without thought, his hands going where they should whilst his thoughts whirlpooled. He didn't even notice when the corpse he was stitching back together was Jason's.

A few days later, when the shock had faded and reality had steadied his unruly reason, Jack visited the optician. He must have something wrong with his eyes. He had a detached retina, that was it. It could be fixed. There had to be an explanation. A cure. He was seeing shadows where there were none and it was affecting his dreams.

Simple.

But the optician told him his eyesight was good. A mild hyperopia. Long-sightedness that was blurring things close up. Well, perhaps that was the answer? Maybe it was intermittent and that was causing...

... the black hearts and the dreams of death.

And the news had already told him his dreams were real. That Corvak and Tennison had indeed crushed and sliced. A minor eyesight issue could not explain that.

Four years in total. More than two dozen occasions. An opening. A black heart that changes quickly to red. A nightmare. Shooting. Stabbing. Rape. Strangulation. Kidnapping.

Not all appeared on the night-time news bulletins or in the newspapers. Not all the horrors came to light. But Jack knew. Jack saw. Jack felt and tasted and heard.

In a mortuary you become immune to many things. The smell of death, stomach contents, antiseptic and decomposition. The sound of a scalpel cutting through flesh or a saw cutting through bone. The sight of a body with its torso opened up and the organs removed. It becomes a job, in the end.

As it was with the black hearts and the nightmares. They were there. Jack could tell the police when he dreamt of a little girl being dragged into a car or an old man being beaten over the head by the teenager for a few coins. He could, but they'd want to know how. They'd think he was involved. Or guilty.

He kept his knowledge to himself. He accepted it. He knew that, when he cut the pericardium and peered inside, the shadow was that of evil. It was the taint of a devil or demon or whatever wickedness evil really was. And, when its job was done and the host was dead, the evil moved on.

Jack let it go.

Caroline. He had stopped giving them other names. Some, the killers, didn't deserve it. Given them pseudonyms was like giving them new identities. They should be known for who and what they were.

Caroline. In life she would have been attractive. Not the sort of girl to be called stunning or gorgeous, but Jack was certain she would have been seen as beautiful. She had graceful lines across her face and figure. She would have drawn stares of desire and jealousy and would not have noticed. It was a shame she had died. A loss to the world.

Incision. Chest plate. Pericardium. Evil, clutching the heart like Corvak would clutch a skull. A dark blanket of night. Of hate. Of murder.

Jack was furious, his acceptance turning to anger. Why defile someone who would not have even thought of committing a crime? Why pollute a person of purity? It was wrong.

And Jack realised why. Because. Just because.

The scalpel was still in his hand and he thrust it forward, piercing the heart, stabbing the mantle of malice. At first nothing happened, then a sharp jolt shot up his arm, knocking him back, releasing his grip on the blade.

A voice behind him: "Are you ok, Jack?"

The pathologist.

Jack reached forward and retrieved the scalpel. The pupils of his eyes were dilated, filling the iris with the same colour that had only seconds before been covering the heart in Caroline's chest.

He turned, a twisted smile on his face.

"Yes, Doctor Adams, I'm fine, thank you."

His hand whipped out, puncturing the left eye of his superior. The man fell backwards, screaming.

Jack advanced, blade held high.

"Everything is fine..."