When Merlin was left to his own devices, he would usually start by roaming the castle's endless corridors, in the hope of coming by somebody he knew, like Gwen. Of course, by this method he risked bumping into people he really didn't like, but Arthur tended to ignore him these days, so it was mostly fine. Also he had not yet tired of the architecture, which was beginning to look glorious now that summer was approaching, for the bright sun made the walls a lovely honey colour. He could sit for hours in one of the alcoves in which the windows were set, watching the events outside, and the slowly-shifting rays of light inside, and the rainbows that were sometimes cast upon the pale walls.

But today his intentions were not exploration. He had set off very pointedly towards the western wing of the castle, which was where the majority of the tournament competitors were being housed, and in the hope of being allowed anywhere near it. Not because he wished to see the celebrities once again – he saw them enough around the place, and was beginning to tire of their pomposity – but because he was on a mission, one that imported on the life of a certain patient back in Gaius's chambers.

The tournament had stopped for lunch, and Merlin's first destination had been his own quarters; it was to here that the man whom Valiant had fought had been carried. He was in a bad state. Gaius could not find a wound that might have caused this condition; he was perplexed by the man's fever, by the immense weakness that had come over him (though he still managed to writhe rather spectacularly, and though he gave little verbal indication, he seemed to be in great pain). Merlin had not said anything. He couldn't. There were other people in the room: to voice his suspicions would get him into trouble, if he was wrong. But Gaius's confusion and alarm were enough to confirm that Valiant had done more than just push the man to the ground: he had done some sort of magic, and it was killing his victim.

Just as the man's condition was reaching a crisis point, Gaius had sent Merlin from the room: the boy was too young to see such a thing as a man in utter agony. Merlin had taken this opportunity to start an investigation. He had to get to Valiant's quarters, and see if there was anything that might provide concrete evidence for the knight's apparent use of magic.

He knew that most of the competitors were currently elsewhere: most of them practising for this afternoon and the following morning, and some of them dulling this morning's pain down the tavern. He had to hope that Valiant would be among the former group. If not, he had a few half-formed plans, most of which exploited his image of complete innocence that tended to charm almost everyone.

When he reached what he believed to be Valiant's room, he knocked on the door and waited a few moments; then, when there was no response, he knelt and looked through the keyhole. There was nobody in. Furthermore the door was not locked. He smiled.

He didn't really know what he expected to find. Perhaps, naive as he was, he thought that all Valiant's secrets might be written down somewhere, in a journal, or a parcel of letters that he would find sitting conveniently in one of the cupboards. Perhaps he had been using magic weaponry, and he would be able to investigate it. The competitors did not practise with their show arms, of course, and Merlin knew he was right even before he saw the sword and shield propped up against the hearth in Valiant's little chamber.

Valiant was evidently not one of those people who, on entering a temporary bedroom, immediately try to make it feel like home. The place was sparse and orderly, and the bed had been made. A single bag lay on the floor, near to the sword, and a set of clothes had been placed upon the counterpane. His complimentary towels were neatly folded on the window-ledge.

This quick glance about the room did not tell Merlin much about the man, except that he was assiduous and almost dull, or at least wanted to seem that way. Therefore he headed straight for the bag and the weapons. Carefully he peered into the bag. It contained just a fat purse, some rolled-up linen and a leather waterskin. Merlin had half-hoped to find a magic wand (despite knowing that such a thing probably did not exist), or some clear evidence that he could use against this enigmatic knight; but nothing. His next hope was in the weaponry.

These had been the ones he had used in the competition; Merlin knew the colours of the shield, and the bright bronze of the sword's hilt. The sword was nothing special, a remarkable fact considering Valiant's apparent wealth and status. Perhaps it was one of those objects that hide their wealth in a sleek stylish appearance that children are not much inclined to recognise as fashionable. But Merlin did not feel as if the sword was important. It had scarcely been used: he knew that much.

The shield however was distinctive, especially since Valiant's yellow and black tunic hardly matched the red field and green snakes emblazoned upon it. It was rather Celtic in design: Merlin knew that Valiant came from north of the Caledonian border, where such artworks abounded, for he had seen them before in the market, and presumed that this was an example of them. But aside from any interest he might have had in the pattern, he felt strangely drawn to it. The hair on the back of his neck was beginning to prickle, as if something was behind him, and he had not yet perceived it with any but his sixth sense; he felt – a strange sensation, like there was – a kindred spirit? – No: he knew what it was, it was magic.

He reached out, drew nearer to the face of one of the snakes –

Suddenly he heard, distinctly, a hissing noise; the eye of the snake seemed to spark; he drew his hand away in a primeval reaction, shaking with subconscious terror. A moment later, and he realised that the sound of footsteps outside had added to his fear: someone was coming.

The deep conviction that it was Valiant clutched at him. He glanced about him; an idea swirled in his mind, and made landfall; in an instant he had cast a spell, and had pattered over to stand by the still-open door, which he could not leave through, for fear of this someone seeing him. And his suspicions about who it was were quickly confirmed, for the footsteps grew louder, and Valiant pushed open the door and entered.

He did not see Merlin for a moment, but, when he did, his angry reaction was startling, and made Merlin jump out of his skin.

'What are you doing here, boy?'

Merlin gulped, and opened his palm, into which he had conjured a flower – a particularly beautiful one that was a combination of a bluebell and a snowdrop, because Merlin's memory was not especially photographic. 'This,' he said, pushing it towards him. 'I was told to give it to you. By a lady.'

'An admirer?' Valiant smirked, and took the flower, a little roughly. 'Does this lady have a name?'

'She... didn't want me to say.'

'No, they never do.' Valiant crossed the room. Merlin noticed his quick glance towards the sword and the shield, and the stare that then pierced the child himself. 'Well! You've done what you came for; run along, boy!'

He had not meant to say it unkindly, but apparently Valiant's nature was not kind, and though his voice was the deep husky sort favoured by certain women, Merlin did not find it at all pleasant. Perhaps this contributed to his hasty flight from the room; perhaps also he was still playing the role of the timid innocent child, an image which, to his shame, he had rather perfected while he had been in Camelot. But at any rate, just after Merlin had left, he heard Valiant go and shut the door, and lock it too, and knew in his heart that he would from then on find it similarly locked. Something was afoot about Knight Valiant, and Merlin felt he had solved the first part of an important mystery.

The conundrum, then, was not what was going on, but rather – how would he begin to explain it to anyone?