ispered, his
eyes tense:

"_The door! Fling it open! I think someone's been listening!_"

Lance switched his alarmed gaze to it. His muscles went taut. The next
moment he had leaped half across the room, jammed back the lock, and
ripped the door wide.

At the other end of the dim passageway he glimpsed a scurrying figure!

Lance sprang after it with a shout to Douglas. Tearing out his
automatic, he flung a burst of lead at the figure, but that instant it
wheeled and sped from sight down another passage. And when Lance got
there, no one was in sight.

* * * * *

For awhile he probed around, desperately, but could find no sign of
anything. The base slept. Sorely troubled, he returned to find the
colonel just coming back from an equally barren search:

"Don't think he heard much," said Douglas grimly. "It must have been
that damned spy who's been getting information of our movements. I'll
have the guards redoubled to prevent him from getting anything
through." He smiled at sight of Lance's anxious face. "No need for too
much worry, Lance! He couldn't have heard much--the walls are
sound-proof and the door fairly tight. Now, you go and rip off some
sleep! You need it! No more work for you till Wednesday night--you're
too important!"

Sleep! Lance only wished he could. But the thrill of what he'd just
heard was too fresh, too new; the blood pumped surgingly through his
veins; his brain whirled with the thought of the glorious enterprise
he and Hay were aiding so vitally.

Then, too, the night was humid and sweaty. For a while Lance lay on
his cot, other sleeping figures to left and right of him, but his own
eyes simply would not stay closed. Finally, after perhaps an hour of
trying to doze off, he arose and, clad only in breeches and
undershirt, wandered outside again with a cigarette glowing in his
mouth.

The war might not have been, the night was so silent. Lance strolled
lazily around the plane hangars, revelling in what little breeze there
was. He seemed to be the only living thing abroad in the night.

Then, suddenly, he flung down his cigarette and ground the butt out
quickly. For he saw he was not the only living thing abroad in the
night. Sliding rapidly away from the end hangar was a dark form!

Lance crouched instinctively and crept forward. Who was the other
wanderer? Not a sentry: they paced a regular beat closer to Douglas'
office. Not another, who, like himself, c