The letter dropped from my hand.

The other facts may be coincidence. A Mr Rose, whom I discovered to be a wealthy relative of the doctor’s, died suddenly that same night—it was said struck by lightning. As far as was known no thunderstorm had occurred in the neighbourhood, but one or two people declared they had heard one peal of thunder. He had an electric burn on him ‘of a curious shape’. His will left everything to his nephew, Dr Rose.

Now, supposing that Dr Rose succeeded in obtaining the secret of the Sixth Sign from Sister Marie Angelique. I had always felt him to be an unscrupulous man—he would not shrink at taking his uncle’s life if he were sure it could not be brought home to him. But one sentence of Sister Marie Angelique’s letter rings in my brain . . . ‘being careful not to close the Circle . . .’ Dr Rose did not exercise that care—was perhaps unaware of the steps to take, or even of the need for them. So the Force he employed returned, completing its circuit . . .

But of course it is all nonsense! Everything can be accounted for quite naturally. That the doctor believed in Sister Marie Angelique’s hallucinations merely proves that his mind, too, was slightly unbalanced.

Yet sometimes I dream of a continent under the seas where men once lived and attained to a degree of civilization far ahead of ours . . .

Or did Sister Marie Angelique remember backwards—as some say is possible—and is this City of the Circles in the future and not in the past?

Nonsense—of course the whole thing was mere hallucination!

Bibliography

Agatha Christie’s short stories typically (but not always) appeared first in magazines and then in her short story books, which tended to be different collections in the UK and the US. This list attempts to catalogue the first publication of each, and gives alternative story titles when used.

THE LAST SÉANCE

First published in the US as ‘The Woman Who Stole a Ghost’ in the November 1926 issue of Ghost Stories, and in the UK as ‘The Stolen Ghost’ in issue 87 of The Sovereign Magazine in March 1927. Reprinted in The Hound of Death and Other Stories (UK, 1933) and Double Sin and Other Stories (US, 1961).

IN A GLASS DARKLY

First published in the UK in the December 1934 issue of Woman’s Journal. Reprinted in The Regatta Mystery and Other Stories (US, 1939) and Miss Marple’s Final Cases and Two Other Stories (UK, 1979).

S.O.S.

First published in the UK in issue 252 of The Grand Magazine in February 1926, and in the US in Ellery Queen’s Mystery Magazine Vol. 10, No. 49, in December 1947. Reprinted in The Hound of Death and Other Stories (UK, 1933) and The Witness for the Prosecution and Other Stories (US, 1948).

THE ADVENTURE OF THE EGYPTIAN TOMB

First published in the UK in The Sketch Number 1600 on 26 September 1923, and in the US as ‘The Egyptian Adventure’ in Blue Book Magazine Vol. 39, No. 4, in August 1924. Reprinted in Poirot Investigates (UK, 1924; US 1925).