Simon was not a really good actor. He overdid the devoted manner.
That conversation I had with Mademoiselle Jacqueline, too, when she pretended that somebody had overheard.
I saw no one.
And there was no one!
But it was to be a useful red herring later.
Then one night on this boat I thought I heard Simon and Linnet outside my cabin.
He was saying,
'We've got to go through with it now.'
It was Doyle all right, but it was to Jacqueline he was speaking.
"The final drama was perfectly planned and timed.
There was a sleeping draught for me, in case I might put an inconvenient finger in the pie. There was the selection of Mademoiselle Robson as a witness - the working up of the scene, Mademoiselle de Bellefort's exaggerated remorse and hysterics.
She made a good deal of noise, in case the shot should be heard.
En verite, it was an extraordinarily clever idea.
Jacqueline says she has shot Doyle; Mademoiselle Robson says so; Fanthorp says so - and when Simon's leg is examined he has been shot.
It looks unanswerable!
For both of them there is a perfect alibi - at the cost, it is true, of a certain amount of pain and risk to Simon Doyle, but it is necessary that his wound should definitely disable him.
"And then the plan goes wrong.
Louise Bourget has been wakeful.
She has come up the stairway and she has seen Simon Doyle run along to his wife's cabin and come back.
Easy enough to piece together what has happened the following day. And so she makes her greedy bid for hush money, and in so doing signs her death warrant."
"But Mr Doyle couldn't have killed her?" Cornelia objected.
"No, the other partner did that murder.
As soon as he can, Simon Doyle asks to see Jacqueline.
He even asks me to leave them alone together.
He tells her then of the new danger.
They must act at once.
He knows where Bessner's scalpels are kept.
After the crime the scalpel is wiped and returned, and then, very late and rather out of breath, Jacqueline de Bellefort hurries in to lunch.
"And still all is not well, for Madame Otterbourne has seen Jacqueline go into Louise Bourget's cabin.
And she comes hot foot to tell Simon about it. Jacqueline is the murderess.
Do you remember how Simon shouted at the poor woman?
Nerves, we thought.
But the door was open and he was trying to convey the danger to his accomplice.
She heard and she acted - acted like lightning.
She remembered Pennington had talked about a revolver. She got hold of it, crept up outside the door, listened and, at the critical moment, fired.
She boasted once that she was a good shot, and her boast was not an idle one.
"I remarked after that third crime that there were three ways the murderer could have gone.
I meant that he could have gone aft (in which case Tim Allerton was the criminal) he could have gone over the side (very improbable) or he could have gone into a cabin.
Jacqueline's cabin was just two away from Dr Bessner's.
She had only to throw down the revolver, bolt into the cabin, ruffle her hair and fling herself down on the bunk.
It was risky, but it was the only possible chance."
There was a silence, then Race asked,
"What happened to the first bullet fired at Doyle by the girl?"
"I think it went into the table.
There is a recently made hole there.
I think Doyle had time to dig it out with a penknife and fling it through the window.
He had, of course, a spare cartridge, so that it would appear that only two shots had been fired."
Cornelia sighed.
"They thought of everything," she said. "It's - horrible!"
Poirot was silent. But it was not a modest silence.