"He had a stain on his jacket." She touched her shoulder, about the place where she would have pinned a corsage. "About here. Quite a large stain, three or four inches across, dark, as if it was wet. He saw me looking at it, only briefly. I suppose that was rude, but it was such an odd place to have a stain so large. He said he had tripped and fallen in the mews. He"-she made a slight gesture as if brushing herself down-"he said he didn't know what he fell in, and would prefer not to think of it. Then he apologized and went on down the road." She glanced at her brother. "If he fell in the mews, then he should have smelled of horse manure."

Barclay's eyes showed not only his disgust but also his impatience. "I daresay he did, Mel!" he said sharply. "Dirt and horse dung." He made a guttural sound in his throat. "I'm perished standing out here. There really isn't anything more to say. Good night, officers."

Melisande refused to move, disregarding his growing anger. "But he didn't!" she insisted. "He didn't smell at all. He was very close to me. He passed only a foot away, and he didn't smell of anything except. . . sweat, and something a little sickly, and . . . something else quite strong, but I didn't recognize it." Again she was looking at Runcorn.

Monk felt a tingle of excitement, the first scent of meaning. He glanced at Runcorn and had to bite his lip to keep silent.

Runcorn let out his breath slowly. "What kind of smell, ma'am?" He was achingly careful not to suggest anything to her. "Can you describe it?"

"Really!" Barclay lost his temper. "What's the matter with you, man? Asking a lady to describe the precise stink of a beggar! I don't know what kind of person you are used to...."

The color washed up Melisande's cheeks. Her brother's rudeness clearly embarrassed her far more than the nature of the question.

Runcorn blushed also-for her, not for himself. Monk could see that in the anger and confusion in his eyes. He longed to help her, and he had no idea how to. Something in her manner, her particular kind of loneliness, had found his sympathy, and he was utterly and wholly in her defense.

Runcorn stared at Barclay with cold dislike. "It matters, sir," he said. His voice was shaking a little, but that could have been attributed to the cold. They were shuddering now, their feet almost numb. "This man may have seen a murder. I don't willingly distress anybody, but it sometimes happens that those who can help the most are also those who are sensitive to the ... unpleasant details."