Hence he lounged about the busy thoroughfare for a quarter of an hour until she returned with the news that Boyne had been home since six o’clock, he having returned unusually early. "Ah! That’s a good sign," said Gerald. "He’ll certainly go out again to-night!" As they strolled together they arranged that Marigold should loiter near the King Street end of the street, while Gerald should stand in an entry near the house which he had used in his previous observations. "If you see me pass into King Street, don’t follow me too closely," he urged, "and at all hazards don’t let him see you. Remember that people who are engaged in crooked business keep their eyes skinned and are always full of suspicion." "I’ll take good care he doesn’t see me," the girl answered him. "Trust me to be discreet." Then they parted, and for about an hour Marigold waited in vain for a sight of her lover. It had now grown quite dark, and the street lamps in Bridge Place were none too brilliant. She was still loitering in the darkness, full of expectation at every footstep on the pavement. At last she again heard footsteps, and a few moments later recognised Boyne’s well-built figure passing within the zone of lamplight across the way. He was walking hurriedly in the direction of King Street, all unconscious that he was being followed. But a few moments later, with noiseless tread—for he wore rubber heels to his shoes—Durrant came along, his eyes searching eagerly for the girl he loved. Suddenly he saw her in the shadow, and realised that she was discreetly following him. The pair exchanged a few words in the crowded King Street, and while Gerald hurried on after Boyne towards the station, the girl followed a little distance behind. They saw him buying a ticket at the station and also purchase a late edition of the evening paper. Then he descended to the platform of the tube and took a train going towards Piccadilly. Gerald and Marigold, who had separated, travelled on the same train until, on arrival at Knightsbridge, the man they were watching alighted. Marigold, who had been on the alert at each station, saw him emerge from the next car, while close behind him was Gerald, with whom, of course, he was unacquainted. Together they followed him along Sloane Street to Pont Street, where he ascended the steps of a smart-looking red-brick house and opened the door with a latchkey. "Now that’s curious!" remarked Gerald when he rejoined the girl. "Did you notice that he entered that house yonder as though it were his own home? I wonder who lives there?" "We must find out," declared Marigold, highly excited at having tracked Mr. Boyne so far. "Yes. But I shall be compelled to watch the house and see what happens now," he said. "I mean to follow him to-night wherever he goes. It almost seems as if he lives here—as well as in Hammersmith!" "Well—he certainly has a latchkey, and this is not a street where they take in lodgers."