Hetherwick laid down his knife and fork with a gesture of finality.
"I'm going to find out who that chap is," he answered. "Got to!"
"You think his visit may have something to do with this?" asked Rhona.
"May, yes. Anyway, I'm not going to let any chance go. There's enough mystery in what you tell me about the man to make it worth while following him up. It must be done."
"How will you do it?"
"You say he said that he was going there again next Friday at the same time? Well, the thing to do, then, is to watch and follow him when he goes away."
"I'm afraid I'm no use for that! He'd know me."
"Nor am I!—I'm too conspicuous," laughed Hetherwick. "If I were a head and shoulders shorter, I might be some use. But I've got the very man—my clerk, one Mapperley. He's just the sort to follow and dog anybody and yet never be seen himself. As you'll say, when you've the pleasure of seeing him, Mapperley's the most ordinary, commonplace chap you ever set eyes on—pass absolutely unnoticed in any Cockney crowd. But he's as sharp as they make 'em, veiling a peculiar astuteness under his eminently undistinguished features. And what I shall do is this—I'll give Mapperley a full and detailed description of Dr. Cyprian Baseverie: I've memorised yours already; Mapperley will memorise mine. Now Baseverie, whoever he may be, will probably go down to Dorking by the 10.10 from here; so will Mapperley. And after Mapperley has once spotted his man, he'll not lose sight of him."
"And he'll do—what?" asked Rhona.
"Follow him to Dorking—watch him—follow him back to London—find out where he goes when he returns—run him to earth, in fact. Then he'll report to me—and we shall know more than we do now, and also what to do next."