As Red silently closed the cabin door behind him, he heard Michael Splendor’s voice within, taking up the mock discussion. The “show” as Don called it, would be quite convincing to any eavesdropper.

And if Don was right in his guess, the spy should be easy to surprise at his work. At that hour of night, no enlisted man would have any legitimate business hanging around the cabin ventilators.

Silent as a shadow, for all his bulk, Red Pennington emerged onto the starlit deck. Slipping aft, he rounded the cabin skylight and probed the shadows under the port rail.

No glimpse of a furtive lurker rewarded him, however. With a grunt of disappointment, he padded forward, heading for the midship’s superstructure.

“I’ll just take a look inside the radio shack,” he muttered under his breath. “Don seems to think that guy Corba’s enlistment was forged—which means he may be the guy who shot at us, too. He’s got a fishy mug, anyway, and his story was a little too slick when we jumped him a few minutes ago!”

The door of the radio shack was on the port side. Therefore, as an extra precaution, Red circled the superstructure to starboard, halting at the corner of the galley.

The space between the deck house and the rail was empty, yet something about it looked queer. For a moment Red stood blinking in puzzlement, trying to make out what was wrong. All at once it came to him.

The radio shack door was open at least two inches; yet no light shone through onto the white deck.

Since Navy men do not go about leaving doors ajar, this suggested one of two things: either Corba had left in a desperate hurry, or he was still inside, with the lights out! Red Pennington intended to find out which.

With the utmost caution, he crept past the galley, noting that the door beyond him did not sway with the gentle roll of the ship. That meant it was propped open deliberately. But why?