Danny’s eyes were fixed on that part of the sky whence the sound seemed to come. This happened to be exactly over the tower of the ruined Abbey, whose black outline stood out distinctly against the stars. Suddenly, like a faint flicker of summer lightning, a white glow appeared for a moment over the tower, as if a bright light had been flashed further down, inside, only visible from above. And between the cracks of the half-ruined walls Danny saw a gleam shine for a moment, and then go out. The detective had had his suspicions about that tower ever since the day he had decided that the artist-spy must have been up there. And yet he had not been able to discover anything about it. Now he was certain something was wrong.
The German spies were there, up in the tower!
They had flashed a light in signal to the aeroplane. Even as he listened breathless, the aeroplane buzzed, as if putting on a higher speed, and then sped off in a southerly direction.
“I’ve got you,” hissed Danny, between his clenched teeth, as he climbed out of the window, and down the rose-covered porch.
He meant to try and find out something more from the ruined Abbey, and then make his report to the Scouts on the night patrol. He, the detective, would lead them to the tower, where his prisoners would be caught like rats in a trap. He would show them the secret passage in the pond. He would explain the drain-pipe telephone. He would identify the prisoners. There would be the bicycle man, and the other in the motor car, and the tramp, and the artist. He, Danny, would be the hero of this adventure.
With beating heart, he crept down the kitchen garden and between the gooseberry bushes. Through the hedge he crawled, and out on to the mossy turf. It was soaking wet with dew. The pale moonlight shone down on the Abbey, giving it a mysterious air, and casting very black shadows. Suddenly Danny remembered his dream. So it was coming true! There was a “traitor” in the Abbey ruin. And he must prove himself to be the gallant crusader of his dream. He gripped the stick he was holding, and it seemed to him to be a long, bright sword. He glanced down at himself, half expecting to see the red Cross of St. George on his breast, the shining armour. But there was only a green jersey and bare, brown knees.
“Yet, I am a knight of St. George—all Scouts and Wolf Cubs are,” he told himself. “Oh, help me to be brave!” he whispered as he stole forward into the shadows. And truly he had need of help—more need than he knew.
Stepping softly into the dark cloisters, Danny held his breath and listened. There was no sound. Slowly he advanced to the door of the tower. Here he flashed on his electric light. The door was fast shut. Then, on the stone floor of the cloister something caught his eye,—wet footprints, as if someone had walked from the dewy grass, on to the smooth grey flags! Kneeling on the ground Danny examined them. They led to the door. Where did they lead from? Here was a chance of discovering how the spies had entered the ruin.
Looking about him warily, Danny crept forward into the darkness, flashing on his light for a moment now and then to see that he was still on the track. About twelve yards on, the footprints suddenly ceased. Glancing around to discover the cause of this, Danny saw that there was a large, jagged hole in the wall, at about the height of his shoulder. The man must have dropped through this into the cloister. In a moment he had clambered through, and found himself standing in the moonlight in that part of the ruin known as the Abbot’s Garden. Beneath his feet was long, dew-soaked grass. How could he discover from what direction the spy had come? Tracking was impossible. He was stumped.
After all, delay might be causing serious danger. He had better retrace his steps quickly, get out of the Abbey, and go to make his report that the spies were in the tower. Turning round to climb back through the hole in the wall, Danny came face to face with something that nearly made his hair stand on end!