“What then?”

“It’s a plant; a deliberate plant to throw suspicion upon Gordon.”

“Why upon Gordon?”

“I don’t know that, unless because Gordon is supposed to have the best possible motive for killing Miss Lamar—­his money troubles—­ and so becomes the logical man to throw the guilt upon.”

“As a matter of fact, Craig, why should the finding of that cigarette case be a cause for suspicion at all?  That’s what I didn’t understand before.”

“Ordinarily it wouldn’t be.  But those open inner doors, the absence of the man in charge—­isn’t it possible that we interrupted an attempt not only to search for the particular damaging pieces of film, but perhaps to destroy the whole?  If some one acted between the time I asked Manton. about the snake film and the moment we arrived in the basement to get it, that some one had to move very fast.”

“In which case it might have been Gordon, after all.  The cigarette stub may have been thrown in lighted to start a fire.  He may not have had time to pick up the case, not knowing just where he dropped it.”

Kennedy shrugged his shoulders.  “It all shows the futility of trying to arrive at a conclusion without definite facts.  That is where science is superior to deduction.”

“It’s all a maze to me just now,” I agreed.

We made our way to the vaults in silence, and, to our surprise, found that they were closed and that even the boy was gone now.  The cellar, as a whole, probably for the purpose of fire protection on a larger scale, was divided into sections corresponding to the units of the buildings above, and this time I noticed that the door through which we had arrived before was closed also.  Had Manton taken fright in earnest at the possibility of fire, or had he given his employees a genuine scare?

We retraced our steps to the yard, and there the alert eye of Kennedy detected a slinking figure just as a man darted into the protection of a doorway.  It was Shirley.  Had he been watching us?  Was he connected in some way with the vague mystery Kennedy seemed to sense in connection with the basement and the film vaults?

Kennedy led the way to the entrance where Shirley had disappeared.  Here there was no sign of him; only steps leading up and down and the open door to a huge developing room.  Returning to the yard, we caught a gesture from the chauffeur of a car standing near by and recognized McGroarty, the driver who had found the ampulla a few days previously.

“Excuse me, Mr. Kennedy,” he apologized, as we approached.  “I should have come to you instead of making you two walk over to me, but it’s less suspicious this way.”

“What do you mean?”

“You recognize me, McGroarty, the chauffeur as found the little bottle?”

Kennedy nodded.

“Well, I says to myself I ought to tell you, but I don’t like to because it might be nothing, you know!”