“Now,” I said, “tell me, if you can, exactly what occurred at the bridge.”

Pierrot pointed to the Swede. “He can tell you more than I,” he said; “obeying your instructions, I followed M. de Lambert at a distance and saw him go down to the bridge. A moment later, I heard the noise of a struggle, and running forward reached the bridge as another man sprang upon it, and, turning aside the assassin’s pistol, saved M. de Lambert’s life. I had almost caught the villain, but he wrenched himself away from me and fled up the bank. You know the rest, monsieur.”

“And now your story, Lenk,” I said, turning to the spy.

“I was coming along by the river, your Excellency,” he replied quietly, “and saw a man, muffled in his cloak, loitering by the bridge in a manner that arrested my attention. Then seeing who it was, I suspected a greater plot than even this.”

“Who was it?” I asked sharply.

The Swede looked at me an instant before he answered. “It was Yury Apraxin,” he said.

“Ah!” I exclaimed softly, knowing at once that he had supposed that the young man was waiting to avenge the czar’s insult, aware of Peter’s careless habit of going unattended.

“So suspicious were his movements,” the spy continued, “that I too loitered about in the shelter of the wall and watched. After a long while M. de Lambert appeared, and walked rapidly towards the bridge. Then I observed that Apraxin had let his mantle fall until he looked almost a woman in the dusk, and it flashed upon me that it was a trick. I ran to the bridge, reaching it just as he stabbed your friend. I caught the fellow’s arm, and he drew his pistol with his left hand. I struck his wrist, and the weapon went off. Pierrot came, and the assassin escaped in the struggle and confusion. That is all, your Excellency.”

“It is to your swift action, then, that we owe M. de Lambert’s life,” I said, looking at him attentively. “What motive prompted you to risk your own for his?”

The Swede’s fair-skinned face flushed, and he returned my look with a flash of feeling in his light eyes.