"No," Hallam agreed, "no driver is going to risk the sack by confessing he gave anyone a lift. Especially a girl. Transport bosses are strict about that. And when it is a case of a girl in trouble of some kind, and when it's the police that are doing the asking, no man in his senses is going to own up to even having seen her." He took the cigarette that Robert offered him. "They needed that lorry driver," he said. "Or someone like him," he added.

"Yes," Robert said, reflectively. "What did you make of her, Hallam?"

"The girl? I don't know. Nice kid. Seemed quite genuine. Might have been one of my own."

This, Blair realised, was a very good sample of what they would be up against if it ever came to a case. To every man of good feeling the girl in the witness box would look like his own daughter. Not because she was a waif, but for the very good reason that she wasn't. The decent school coat, the mousy hair, the unmadeup young face with its appealing hollow below the cheek-bone, the wide-set candid eyes-it was a prosecuting counsel's dream of a victim.

"Just like any other girl of her age," Hallam said, still considering it. "Nothing against her."

"So you don't judge people by the colour of their eyes," Robert said idly, his mind still on the girl.

"Ho! Don't I!" said Hallam surprisingly. "Believe me, there's a particular shade of baby blue that condemns a man, as far as I'm concerned, before he has opened his mouth. Plausible liars every one of them." He paused to pull on his cigarette. "Given to murder, too, come to think of it-though I haven't met many killers."

"You alarm me," Robert said. "In the future I shall give baby-blue eyes a wide berth."

Hallam grinned. "As long as you keep your pocket book shut you needn't worry. All Baby-Blue's lies are for money. He only murders when he gets too entangled in his lies. The real murderer's mark is not the colour of the eyes but their setting."

"Setting?"