A suspicion crossed my mind that Mrs. Franklin rather liked playing different roles. At this moment she was being the loyal and hero-worshipping wife. She leaned forward, placing an earnest hand on Poirot's knee.

"John," she said, "is really a - a kind of saint. It makes me quite frightened sometimes."

To call Franklin a saint was somewhat overstating the case, I thought, but Barbara Franklin went on, her eyes shining:

"He'll do anything - take any risk - just to advance the sum of human knowledge. That is pretty fine, don't you think?"

"Assuredly, assuredly," said Poirot quickly. "But sometimes, you know," went on Mrs. Franklin, "I'm really nervous about him. The lengths to which he'll go, I mean. This horrid bean thing he's experimenting with now. I'm so afraid that he'll start experimenting on himself."

"He'd take every precaution, surely," I said. She shook her head with a slight, rueful smile. "You don't know John. Did you never hear about what he did with that new gas?" I shook my head.

"It was some new gas they wanted to find out about. John volunteered to test it. He was shut up in a tank for something like thirty-six hours - taking his pulse and temperature and respiration - to see what the aftereffects were and if they were the same for men as for animals. It was a frightful risk, so one of the professors told me afterwards. He might easily have passed out altogether. But that's the sort of person John is - absolutely oblivious of his own safety. I think it's rather wonderful, don't you, to be like that? I should never be brave enough."

"It needs, indeed, high courage," said Poirot, "to do these things in cold blood." Barbara Franklin said:

"Yes, it does. I'm awfully proud of him, you know, but at the same time it makes me rather nervous, too. Because, you see, guinea pigs and frogs are no good after a certain point. You want the human reaction. That's why I feel so terrified that John will go and dose himself with this nasty ordeal bean and that something awful might happen." She sighed and shook her head. "But he only laughs at my fears. He really is a sort of saint, you know."

At this moment Boyd Carrington came towards us.

"Hullo, Babs, ready?"

"Yes, Bill, waiting for you."

"I do hope it won't tire you too much."

"Of course it won't. I feel better today than I have for ages." She got up, smiled prettily at us both, and walked up the lawn with her tall escort.

"Dr. Franklin - the modern saint - h'm," said Poirot.

"Rather a change of attitude," I said. "But I think the lady is like that."

"Like what?"

"Given to dramatizing herself in various roles. One day the misunderstood neglected wife, then the self-sacrificing suffering woman who hates to be a burden on the man she loves. Today it's the hero-worshipping helpmate. The trouble is that all the roles are slightly overdone."