“I mean this.  The police have been combing the underworld for him; I don’t think he comes from there.  I think they’ve got to look higher, up in our world, for a brilliant man with a kink in the brain.  He may be a Doctor, a lawyer, a merchant, honored in his community by day—­good line that, I’ll use it some time—­and at night, a bloodthirsty assassin.  Deacon Brodie—­ever hear of him —­the Scotch deacon that burgled his parishioners’ houses on the quiet?  Well—­that’s our man.”

“But my Lord, Bill—­”

“I know.  I’ve been going around the last month, looking at everybody I knew and thinking—­are you the Bat?  Try it for a while.  You’ll want to sleep with a light in your room after a few days of it.  Look around the University Club—­that white-haired man over there—­dignified—­respectable—­is he the Bat?  Your own lawyer—­your own Doctor—­your own best friend.  Can happen you know—­look at those Chicago boys—­the thrill-killers.  Just brilliant students—­likeable boys—­to the people that taught them—­and cold-bloodied murderers all the same.”

“Bill!  You’re giving me the shivers!”

“Am I?” The edit or laughed grimly.  “Think it over.  No, it isn’t so pleasant.—­But that’s my theory—­and I swear I think I’m right.”  He rose.

His companion laughed uncertainly.

“How about you, Bill—­are you the Bat?”

The editor smiled.  “See,” he said, “it’s got you already.  No, I can prove an alibi.  The Bat’s been laying off the city recently—­ taking a fling at some of the swell suburbs.  Besides I haven’t the brains—­I’m free to admit it.”  He struggled into his coat.  “Well, let’s talk about something else.  I’m sick of the Bat and his murders.”

His companion rose as well, but it was evident that the editor’s theory had taken firm hold on his mind.  As they went out the door together he recurred to the subject.

“Honestly, though, Bill—­were you serious, really serious—­when you said you didn’t know of a single detective with brains enough to trap this devil?”

The editor paused in the doorway.  “Serious enough,” he said.  “And yet there’s one man—­I don’t know him myself but from what I’ve heard of him, he might be able—­but what’s the use of speculating?”

“I’d like to know all the same,” insisted the other, and laughed nervously.  “We’re moving out to the country next week ourselves —­right in the Bat’s new territory.”

“We-el,” said the editor, “you won’t let it go any further?  Of course it’s just an idea of mine, but if the Bat ever came prowling around our place, the detective I’d try to get in touch with would be—­” He put his lips close to his companion’s ear and whispered a name.