"He's a tall, slim fellow with the keenest eyes you ever saw in a human head; but those eyes mean mischief and death."

"And you?"

"Oh, sir, I'm Mag of the Dusthole. I'm out for wictims; but I saw him watching you, and I couldn't help wanting to spoil his game."

"You don't know him, then?"

"I know him, and that's why I want to bring his schemes to naught. It's Jem—Jem, the Sydneyite."

"I have no such enemy by that name."

"Mebbe not; but he's watching you, all the same. He used to live in Sydney, Australia, and——"

The detective started.

"In Australia?" broke in Old Broadbrim.

"Yes, yes. He came back from there a year ago, and has been lording it over some people in London ever since. He's cool-headed, and has the softest fingers you ever saw. Jem's a bad one."