Joaniel's expression softened and she pointed to a nurses' station in the centre of the chamber.

'There. My deputy, Ardelia, will try to find him for you, though you should be prepared for the fact that he may be dead.'

'As the Emperor wills,' said Uriel. The corner of the woman's mouth twitched at the familiar phrase and she nodded.

'Now, if you will excuse me, I have work to do,' she said and turned away.

Uriel watched Sister Joaniel Ledoyen limp towards the next bed and the next bloodstained soldier, then turned on his heel and marched to the nurses' station.

It took an hour to locate Pavel Leforto. The bed Ardelia first indicated held only a pitiful wretch whose burned face was encased in gauze bandages, but was obviously not Pavel as his shoulder was uninjured. Eventually, Uriel located him on the second floor of the building, his upper shoulder and neck wrapped tightly in a plasflesh bandage. An intravenous drip bag was wedged under his arm - presumably to keep it from freezing - which in turn was draped outside the sheets to allow the liquid in the bag to flow.

His eyes were closed, but his breathing was deep and even. Even Uriel's limited knowledge of human physiology told him that Pavel Leforto would live, though he would have a vivid scar to remind him of his battle with the tyranids. Uriel remembered the last time he had seen Pavel's face, screaming and contorted in agony as Pasanius had rushed him back to the triage station. His features were at peace now, oblivious to the cries echoing from the floor below and the miasma of death that filled this place.

Clutched in the sleeping man's hand was a hololithic slate, and Uriel bent to lift it, seeing the image of a homely, but attractive woman with two beaming children clutched close to her. Uriel stared at the picture for several minutes, seeing the love these people had for this man through the grainy image. Pavel Leforto had a family to cleave to, a home to defend and a future to protect.

Things he could never have.

Replacing the picture, Uriel removed a purity seal from his armour and set it on Pavel's chest, before retreating from the bed, unwilling to disturb the wounded soldier's rest. He left the - upper floor and made his way down to the medicae building's vestibule. Through a low arch to his left he saw a small passageway that led to an open doorway, from which a warm, softly glowing light spilled. He caught the soothing scent of incense over the stench of blood and stepped through the arch and into the medicae building's small chapel.

Simple and elegant, the chapel was spartanly furnished, the only concession to ostentation a semi-circular stained glass window depicting sisters of the Order Hospitaller ministering to the sick and providing alms to the needy. Uriel felt a peace and serenity he had not experienced in many months, as though a dark shadow that smothered the better angels of his nature could not violate this holy place.

He closed the door and walked to the end of the nave, bowing to the effigy of the Emperor and kneeling beneath His majestic gaze.

'Emperor of Mankind, in this time of war I seek the solace that only you can provide. Too often I feel hate poisoning my dreams. A darkness gathers in me and I fear for my soul in the coming days. Help me to overcome the taint that was placed within me and save me from becoming that which I have spent my entire life fighting in your name.'

Uriel took a shuddering breath and said, 'I am afraid that I may soon lose sight of what it is to serve you, that I am not worthy of your love.'

'No, Captain Ventris,' said a voice behind him. 'All who serve the Emperor are worthy of that.'

Uriel spun, rising to his feet. Sister Joaniel stood framed in the light from the window, the warm colours imparting a ruddy, healthy glow to her skin.

'Sister,' said Uriel. 'I did not notice you.'

'I know, I'm sorry for disturbing you. Would you like me to go?'

'No, no, of course not.'

'Then may I join you?'

'Yes, please do.'

Sister Joaniel nodded and limped to the end of the nave, genuflecting before the Emperor's statue and wincing as her hip joint cracked noisily. She sat on the front pew and said, 'I often come here when I have time. It is very peaceful.'

'It is,' agreed Uriel moving to join her on the pew, dwarfing the Adepta Sororitas nurse. The timber creaked under his bulk. 'I felt as though a great weight might unburden itself from me here.'

'You carry a burden?' asked Joaniel.

Uriel did not answer, his eyes cast down at the polished wooden floor. Eventually he said, 'You heard what I was saying when you came in.'

'True, but I do not know what you were referring to. Would you like to talk about it? I have counselled a great many warriors who carried emotional wounds as well as physical. Trust me, it can be very cathartic to give voice to thoughts that trouble you.'

'I do not know, sister… I am… not good at expressing such things.'

'Does it have something to do with the soldier you came to see?'

'No, more to do with a monstrous alien I fought on a distant world.'

'What kind of alien, a tyranid?'

Uriel shook his head. 'No. To this day I am not exactly sure what it was. All I know is that it was an ancient creature, old when the galaxy was young, that lived for slaughter and revelled in murder. An inquisitor I knew called it the Bringer of Darkness, and such a name was aptly given, for it could reach into a man's thoughts and drag his basest instincts to the fore.'

Uriel's hands began to shake as he relived the battle beneath the world on Pavonis. 'I saw men rend and tear themselves apart in an orgy of bloodletting and I felt my own urge to kill driven to new heights that sicken me to this very day. Visions of madness and death surrounded the creature and when its mind briefly touched mine, I saw everything, all the slaughter in the universe, and it bathed my soul in blood.'

'But you defeated it?'

'After a fashion. We drove it away and lived to tell the tale, though what became of it, I do not know.'

'You are haunted by the things it showed you,' stated Joaniel.

'Aye,' nodded Uriel, placing his head in his hands. 'I close my eyes and all I see is blood, death and mutilation. When I fight, I can barely hold back the killing rages born from the taint of the Bringer of Darkness.'

'I do not pretend to understand the nature of this monstrous being, but I feel you are tormenting yourself needlessly, Uriel. 'To have your mind touched, however briefly, by something of such power is bound to leave scars. To believe otherwise is folly.'

Joaniel reached out and took Uriel's hand. 'Every injury, whether physical or psychological, leaves behind its mark and sometimes they come tumbling out like daemons in the dark. Scars heal, Uriel, but only if you let them.'

'You do not think I am tainted?'

Joaniel smiled. 'No, I do not, Uriel. The power of this Bringer of Darkness must have been prodigious, but you defeated it. Yes, it showed you the depths to which man can sully himself with blood and death, but such barbarity is in all of us. You must accept that aspect of yourself and understand that part of the Bringer of Darkness will always be with you. With acceptance will come release. That you feel such pain tells me you are not tainted.'

Uriel nodded, already feeling the shadow within him recede at Joaniel's words. The two sat in companionable silence for many minutes until the vox bead in his ear crackled into life and the clipped tones of Learchus said, 'Brother-Captain, your presence is required at the main wall.'

He stood, acknowledging the message and bowed to the seated woman. 'My thanks for your understanding, Sister Joaniel,' said Uriel. 'But I must go now.'

Joaniel pushed herself from the pew and offered him her hand. Uriel shook it, his gauntlet swallowing her delicate hand utterly.