The noise of the passing train had scarcely died away, when from just behind them the hideous shriek of Mac Alarney's motor-horn rose blastingly three times upon the night air, the last fainter than the others, as if the pursuing car had dropped back. "He's beaten! He couldn't keep up the pace, much less better it," Blaine remarked. "Those three blasts sounded a warning to the guards of the retreat. It was probably a signal agreed upon in case of danger. We're in for it now!" They swerved abruptly, between two high stone gateposts, and up a broad sweep of graveled driveway. Lights gleamed suddenly in the windows of the hitherto darkened house, which loomed up gaunt and squarely defined against the sullen sky. "Your men, in the other cars--" Doctor Alwyn stammered, as they came to a crunching stop before the door. "Will they arrive in time to be of service? Mac Alarney will reach here first--" "My men will be at his heels," returned Blaine, shortly. "They held back purposely, acting under my instructions. Come on now." He sprang from the car and up the steps, and the Doctor found himself following, with Ross and Suraci on either side. The driver turned their car around and ran it upon the lawn, its searchlight trained on the circling drive, its engine throbbing like the throat of an impatient horse. In response to the detective's vigorous ring, the door was opened by a short, stocky man, at sight of whom the Doctor gave a start of surprise, but did not falter. The man was clad in the white coat of a hospital attendant, beneath which the great, bunchy muscles of his shoulders and upper arms were plainly visible. "Hello, Al!" exclaimed Blaine, briskly. The veins on the thick bull neck seemed to swell, but there was no sign of recognition in the stolid jaw. Only the lower lip protruded as the man set his jaw, and the little, close-set, porcine eyes narrowed. "You were a rubber at the Hoffmeister Baths the last time I saw you," went on the detective, smoothly, as he deftly inserted his foot between the door and jamb. "You remember me, of course. I'm Henry Blaine. My friends and I have come here to-night on a confidential errand, and I'd like a word in private with you." The man he called "Al" muttered something which sounded like a disclaimer. Then he caught sight of the Doctor's face over Blaine's shoulder, and a spasm of black rage seized him. "Oh, it's you, is it? You've snitched, d--n you! I'll do for you, for this!" He lunged forward, but Blaine, with a strength of which the Doctor would not a moment before have thought him possessed, grasped the ex-rubber and flung him backward, advancing into the hall at the same time, while his two operatives and the Doctor crowded in behind him.