A third whistle, this time a little deeper and in a different note. And, above their heads, the noise grew louder, more hurried.
"It sounds rather as if it were on the balcony of the boudoir," whispered Shears.
He put his head between the glass doors, but at once drew back with a stifled oath. Wilson looked out in his turn. Close to them, a ladder rose against the wall, leaning against the balustrade of the balcony.
"By Jove!" said Shears. "There's some one in the boudoir. That's what we heard. Quick, let's take away the ladder!"
But, at that moment, a form slid from the top to the bottom, the ladder was removed and the man who carried it ran swiftly toward the railings, to the place where his accomplices were waiting. Shears and Wilson had darted out. They came up with the man as he was placing the ladder against the railings. Two shots rang out from the other side.
"No," replied Wilson.
He caught the man around the body and tried to throw him. But the man turned, seized him with one hand and, with the other, plunged a knife full into his chest. Wilson gave a sigh, staggered and fell.
"Damnation!" roared Shears. "If they've done for him, I'll do for them!"
He laid Wilson on the lawn and rushed at the ladder. Too late: the man had run up it and, in company with his accomplices, was fleeing through the shrubs.