Carton and Ellsworth stared at him blankly, but Grantham's eyes gleamed with sudden understanding.
"The third fact, which I also learned last night and which is the most significant perhaps of all, is the simple record of a stockbroker's account carried some weeks ago by Mr. Peter Harkness."
Wade was silent, and Carton, astounded and bewildered, could only stare at him still. Ellsworth was about to burst into questions but was interrupted by Grantham's voice. The physicist had risen and turned from them toward the window. His voice came over his shoulder to them.
"I think I can give you a fourth fact that will clinch it, Wade." His right arm crooked—
Wade leapt, but an instant too late. For when he spun Grantham around the physicist was already falling, his lips writhing with cyanide grains still upon them, a faint peachy odor in the air. He was still, dead, when Wade lowered his body to the floor. The detective straightened, mopping his brow.
"I was afraid of that," he panted. "I was afraid of it—but damned if I don't think it was his best way out!"
Carton and Ellsworth gazed as though petrified. Then Carton's voice—shaking—
"Then Grantham—Grantham himself—was the Invisible Master?"
Wade turned.
"There never was any Invisible Master at all," he said.