Almost at the same time he realised that the situation was a complicated one. There was the question of the spy, von Preussen. The R.A.F. officers would, on their release, certainly demand an explanation of their supposed comrade's whereabouts, and then the spy would be revealed in his true character. It would be awkward--decidedly awkward--for von Preussen, but in his vindictiveness against the mutineering crew von Preugfeld swept aside the question. He had little qualms in sacrificing von Preussen to attain his immediate aim. "What officers are they?" demanded Morpeth. He pictured the plight of master mariners of Mercantile Marine held captive on board the submarine that had sent their vessel to the bottom--hostages who, contrary to all the recognised canons of war, had been compelled to run a grave risk of being slaughtered by their fellow countrymen while in the hold of a modern pirate submarine. "Von der Air Regiment at Auldhaig," replied von Preugfeld. "It fair capture vos," he hastened to explain. "We know most of them," exclaimed Meredith. "I wonder who they are?" Morpeth as inquisitor-in-chief put the question, but von Preugfeld shook his head and professed ignorance on the matter. With a gesture Morpeth dismissed him. Shivering with cold and trembling with rage, the kapitan of U 247 disappeared below, to enjoy a far greater hospitality than he had ever bestowed upon his prisoners of war. Meanwhile Q 171, running at thirty knots, was fast overhauling the mutineers. In forty minutes after von Preugfeld's rescue the conning-tower of the fugitive was sighted at a distance of five miles. Morpeth immediately rang down for fifteen knots. The enormous speed of the Q-boat would be sufficient to cause surprise and suspicion in the minds of the U-boat's crew, and supposing it were another submarine which could dive and succeed in getting away, then the story of a decoy capable of attaining a terrific pace would be known to the German Admiralty. In that case Morpeth's "little stunt" would bid fair to become a "wash-out." Ten minutes later the White Ensign was hoisted at Q 171's masthead, and a shell, purposely fired wide, threw up a column of water fifty yards from the U-boat's port bow. "That's done the trick," exclaimed Wakefield, as a white flag was promptly hoisted on the mutineer. "It's 'Kamerad' all the time when they're cornered. By Jove! the old blighter did speak the truth for once. There are fellows in khaki standing aft." Morpeth merely grunted. He was pondering in his mind--not on the question of how to deal with his prize, but one on which weightier matters depended. It meant an addition of thirty odd people to feed and quarter--a big proposition indeed. CHAPTER XIX THE TABLES TURNED "WHAT'S for dinner at the mess to-night?" inquired Blenkinson. "Wonder if the management has got rid of our box for 'The Maid of the Mountains'? If not, will he try and make us pay up?"