Making a rapid survey of the household bedrooms he found an irritating normality.
In Phillipa Haymes' room were photographs of a small boy with serious eyes, an earlier photo of the same child, a pile of schoolboy letters, a theatre programme or two.
In Julia's room there was a drawer full of snapshots of the South of France.
Bathing photos, a villa set amidst mimosa. Patrick's held some souvenirs of Naval days.
Dora Bunner's held few personal possessions and they seemed innocent enough.
And yet, thought Fletcher, someone in the house must have oiled that door.
His thoughts broke off at a sound below stairs.
He went quickly to the top of the staircase and looked down.
Mrs. Swettenham was crossing the hall. She had a basket on her arm.
She looked into the drawing-room, crossed the hall and went into the dining-room.
She came out again without the basket.
Some faint sound that Fletcher made, a board that creaked unexpectedly under his feet, made her turn her head.
She called up:
"Is that you, Miss Blacklog?"
"No, Mrs. Swettenham, it's me," said Fletcher.
Mrs. Swettenham gave a faint scream.
"Oh! how you startled me.
I thought it might be another burglar."
Fletcher came down the stairs.
"This house doesn't seem very well protected against burglars," he said.
"Can anybody always walk in and out just as they like?"
"I just brought up some of my quinces," explained Mrs. Swettenham.
"Miss Blacklog wants to make quince jelly and she hasn't got a quince tree here.
I left them in the dining-room."
Then she smiled.
"Oh, I see, you mean how did I get in?
Well, I just came in through the side door.
We all walk in and out of each other's houses, Sergeant.
Nobody dreams of locking a door until it's dark.
I mean it would be so awkward, wouldn't it, if you brought things and couldn't get in to leave them?
It's not like the old days when you rang a bell and a servant always came to answer it."
Mrs. Swettenham sighed.
"In India, I remember," she said mournfully, "we had eighteen servants - eighteen.
Not counting the ayah.
Just as a matter of course.
And at home, when I was a girl, we always had three although Mother always felt it was terribly poverty stricken not to be able to afford a kitchen-maid.
I must say that I find life very odd nowadays. Sergeant, though I know one mustn't complain.
So much worse for the miners always getting psittiscosis (or is that parrot disease?) and having to come out of the mines and try to be gardeners though they don't know weeds from spinach."
She added, as she tripped towards the door,
"I mustn't keep you.
I expect you're very busy.
Nothing else is going to happen, is it?"
"Why should it, Mrs. Swettenham?"
"I just wondered, seeing you here.
I thought it might be a gang.
You'll tell Miss Blacklog about the quinces, won't you?"
Mrs. Swettenham departed.
Fletcher felt like a man who has received an unexpected jolt.
He had been assuming - erroneously, he now perceived - that it must have been someone in the house who had done the oiling of the door.
He saw now that he was wrong.