“Most,” admitted Mannering, and something more than the humour of the situation was gleaming in his eyes.

“Supposing a man came through the window?” asked Lorna.

“It doesn’t make any difference, my dear. I tell you the door’s never locked unless I’m here. Still, that doesn’t matter now. Mannering, have a look at these. . . .”

While he talked, and while Mannering recovered from the effect of the “that doesn’t matter” — could anything matter as much to him as that comprehensive explanation of the first essential for getting at the strong-room without sending the alarm off? — Fauntley had been manipulating the leather case. Now he unlocked it, with a key taken from a ring in his pocket. The light from the single electric lamp in the strong-room seemed to shiver and give fire. The room was a blaze of twinkling lights, of gold and silver and a thousand colours that were never still.

The light shone on diamonds set in the black velvet of the case. A single-piece tiara held the centre, glittering and blazing; rings surrounded it, while beneath it was a necklace, bordered by bracelets that dangled so often on Lady Fauntley’s plump wrists. The room was alive!

“Well?” breathed Fauntley.

“Terrific!” muttered Mannering. “I’d no idea you’d anything like this, Fauntley. Wonderful!”

“Watch this,” said Fauntley.

He was a bundle of excitement as he peered at the stones, and his hands trembled. Lady Fauntley was breathless. Lorna said nothing, and the fire danced from the diamonds to her eyes. Mannering found the spell of the diamonds almost too much for him; for the first time he stopped repeating to himself the numbers of the combination. He’d never forget them now. God! What an idea — cracksmanship!

Fauntley took a pocket-lamp from a shelf in the room and flicked the light on as he held the glass close to the stones. As it travelled, within a few inches of the collection, the diamonds seemed to move like living fire. Shimmering and cascading, fascinating and compelling, they lived.