Very quietly he reached out to the stand at his elbow, got his revolver and his flashlight, and slipped to the floor. The malefactor without was approaching the window. Another flash of lightning would have revealed much to Banneker had he not been crouching close under the sill, on the inside, so that the radiance of his light, when he found the button, should not expose him to a straight shot.

A hand fumbled at the open window. Finger on trigger, Banneker held up his flashlight in his left hand and irradiated the spot. He saw the hand, groping, and on one of its fingers something which returned a more brilliant gleam than the electric ray. In his crass amazement, the agent straightened up, a full mark for murder, staring at a diamond-and-ruby ring set upon a short, delicate finger.

No sound came from outside. But the hand became instantly tense. It fell upon the sill and clutched it so hard that the knuckles stood out, white, strained and garish. Banneker’s own strong hand descended upon the wrist. A voice said softly and tremulously:

“Please!”

The appeal went straight to Banneker’s heart and quivered there, like a soft flame, like music heard in an unrealizable dream.

“Who are you?” he asked, and the voice said:

“Don’t hurt me.”

“Why should I?” returned Banneker stupidly.

“Some one did,” said the voice.

“Who?” he demanded fiercely.