Then on the porch, a loose board creaked.
Gabriel sprang to his feet.

The others stood up and faced the door.
"In heaven's name, what's that outside ?" demanded Craig.
On the instant, a heavy foot crashed through the panels of their door.
The door, burst open, flew back.
In the aperture, stood a man, in aviator's dress, with another dimly visible behind him.

Both these men held long, blue-nosed, oxygen-bullet-shooting revolvers levelled at the little group around the table.
"My God! Air Trust spies!" cried Grantham, pale as death.
"Hands up, you!" shouted the man in the doorway, with a wild triumph in his voice.

"You're caught, all of you! Not a move, you -- -- -- -- -- --! Hands up!".