"S-sh!" he whispered warningly, laying his fingers on her lips, as she would have spoken. "Nobody must know I am here till to-morrow. That is why I came aboard like that. Listen. Your cousin, Sir Ernest Scrivener, alias Marmaduke Moorsdyke, is here, and is plotting to kidnap you. There is a traitor somewhere on this yacht who supplies him with all information. The attempt is to be made to-night."
"To-night!" murmured Lady Margaret in horror. "What am I to do? His ingenuity is dev—er—fiendish."
"It shall be baffled," replied Ralph reassuringly. "I have thought it all out. It would be dangerous for you to leave the yacht because, in view of to-morrow's race, neither your brother nor I could accompany you. There is only one place on board where you can pass the night in assured safety—the crow's-nest."
"The crow's-nest," repeated Lady Margaret, clapping her hands. "What fun! I shall be rocked to sleep beautifully, and of course they will never think of looking for me there."
"Come," said Ralph, taking her hand. "There is no time to lose, and none of the crew must be allowed to see you. We don't know whom we can trust."
Snatching her in his arms, he carried her easily up the frail rigging, his mountain training showing in every step he took. Five minutes later he returned alone and dropped noiselessly to the deck. He looked round cautiously; there was nobody in view except Lord Tamerton.
"It's all right, Fred," he whispered. "Let us turn in."
They descended the broad staircase arm-in-arm. No sooner had they disappeared than a dark figure crept with a low chuckle from underneath a coil of rope and dropped silently over the yacht's counter.
A phosphorescent gleam disturbed the darkness of the water.