ngrily. "I don't want you
interfering in my affairs!"

The detective smiled quietly. Then a new expression suddenly tightened
his lips.

"Never mind about that just now!" he exclaimed. "See here, take this
police whistle from my left hand, quick, and blow it for all that you
are worth!"

It was characteristic of Tavernake that he was prepared to obey without
a second's hesitation. The opportunity, however, was denied him. The
events which followed came and passed like a thought. A blow on his left
wrist and the whistle fell into the road. A dark figure had sprung up,
apparently from space; a long arm was twined around Pritchard's neck,
bending him backwards; there was a gleam of steel within a few inches of
his throat. And then Tavernake saw a wonderful thing. With a turn of his
wrist, Pritchard suddenly seemed to lift the form of his assailant into
the air. Tavernake caught a swift impression of a man's white face, the
head pointing to the street, the legs twitching convulsively. Head
over heels Pritchard seemed to throw him, while the knife clattered
harmlessly into the roadway. The man lay crumpled up and moaning before
the door of one of the houses. Pritchard sprang after him. The door had
been cautiously opened and the man crawled through; Pritchard followed;
then the door closed and Tavernake beat upon it in vain.

For several seconds--it seemed to Tavernake much longer--he stood
gazing at the door, breathing heavily, absolutely unable to collect his
thoughts. The whole affair had happened with such amazing celerity! He
could not bring himself to realize it, to believe that it was Pritchard
who had been with him only a few seconds ago, who in danger of his
life had performed that marvelous trick of jiu-jutsu, had followed
his unknown assailant into that dark, mysterious house, from no single
window of which was a single gleam of light visible. Tavernake had led
an uneventful life. Of the passions which breed murder and the desire
to kill he knew nothing. He was dazed with the suddenness of it all. How
could such a thing happen in the midst of London, in a thoroughfare only
momentarily deserted, at the further end of which, indeed, were many
signs of life! Then the thought of that knife made him shiver--blue
glittering steel cutting the air like whipcord. He remembered the look
in the assassin's face--horrible, an epitome of the passions, which
seemed to reveal to him in that moment the existence of some other,