“I was going to say here’s this lady, deceased’s sister, giving him patent medicines. Here’s the Sage affair, the chemist, a member of the advanced party that threatened deceased, supplying them. Here’s the doctor that gave the anæsthetic turning up at the same meeting as the chemist and the nurse that gave the injection. The nurse knows the chemist; the chemist, so Mr. Bathgate says, isn’t so keen to know the nurse. The doctor, seemingly, knows neither of them. Well now, that may be bluff on the doctor’s part. Suppose they were all working in collusion? Sage wouldn’t be very keen on associating himself with Nurse Banks. Dr. Roberts might think it better to know neither of them. Suppose Sage had supplied Miss O’Callaghan with a drug containing a certain amount of hyoscine, Nurse Banks had injected a bit more, and Dr. Roberts had made a job of it by injecting the rest?”

“All of them instructed by Comrade Kakaroff?”

“Well—yes.”

“But why? Why involve three people when one might do the trick? And anyway, none of them knew O’Callaghan was going to throw a fit and lie-for-dead in the House of Commons and then be taken to Sir John Phillips’s nursing-home.”

“That’s so, certainly, but Sage would know, through Miss O’Callaghan, that her brother intended having Sir John to look at him as soon as the Bill was read. It seems they knew it was appendix. Mightn’t they even have said he’d better go to the hospital and have it out? The lady tells Mr. Sage about this. He reports. He and Nurse Banks and Dr. Roberts think they’ll form a plan of action.”

“And, lo and behold, it all comes to pass even as they had said. I don’t like it, Fox. And anyway, my old one, how did Dr. Roberts give the injection with no syringe? Why didn’t he take the golden opportunity of exercising his obvious right of giving the hypodermic? To establish his innocence, you will say. He gave it on the sly, all unbeknown. But how? You can’t carry a syringe all ready for use, complete with lethal dose, in your trouser pocket. And anyway, his trousers like all the rest of him, were covered with a white nightie. And he was never alone with the patient.”

“That’s so, and I admit it’s a bit of a facer. Well—perhaps he simply arranged the matter with Miss Banks and she gave the injection, using hyoscine instead of camphor.”

“Subsequently letting everyone know how delighted she was at the death. Do you think that was subtlety or stupidity?”

Fox shook his head solemnly.

“I don’t say I support the theory, chief, but it is a theory.”