was just after the Japanese earthquake, and the explanation given was that the disaster was the result of

a tidal wave. Now, a short time ago, a round-up was

made of certain crooks and gunmen, and with them

were captured some papers which put an entirely new

face upon the matter. They appeared to refer to some

organisation called the 'Big Four,' and gave an incomplete description of some powerful wireless installation

--a concentration of wireless energy far beyond anything so far attempted, and capable of focusing a beam

of great intensity upon some given spot. The claims

44 Agatha Christie

made for this invention seemed manifestly absurd, but I

turned them in to headquarters for what they were

worth, and one of our highbrow professors got busy on

them. Now it appears that one of your British scientists read a paper upon the subject before the British Association. His colleagues didn't think great shakes of it, by

all accounts, thought it far-fetched and fanciful, but

your scientist stuck to his guns, and declared that he

himself was on the eve of success in his experiments."

"Eh, bien?" demanded Poirot, with interest.

"It was suggested that I should come over here and

get an interview with this gentleman. Quite a young

fellow, he is, Halliday by name. He is the leading authority on the subject, and I was to get from him

whether the thing suggested was anyway possible."

"And was it?" I asked eagerly.

"That's just what I don't know. I haven't seen Mr.

Halliday--and I'm not likely to, by all accounts."

"The truth of the matter is," said Japp, shortly, '' Halliday's disappeared.''

"When?"

"Two months ago."

"Was his disappearance reported?"

"Of course it was. His wife came to us in a great

state. We did what we could, but I knew all along it

would be no good."

"Why not?"

"Never is--when a man disappears that way." Japp winked.

"What way?"

"Paris."

"So Halliday disappeared in Paris?"

"Yes. Went over there on scientific work--so he said. Of course, he'd have to say something like that. But you know what it means when a man disappears over there.

FR1;THE BIG FOUR 45

Either it's Apache work, and that's the end of it--or

else its voluntary disappearance--and that's a great deal the commoner of the two, I can tell you. Gay Paree and

all that, you know. Sick of home life. Halliday and his

wife had had a tiff before he started, which all helps to make it a pretty clear case.''

"I wonder," said Poirot thoughtfully.

The American was looking at him curiously.

"Say, mister," he drawled, "what's this Big Four idea?"

"The Big Four," said Poirot, "is an international organisation which has at its head a Chinaman. He is

known as Number One. Number Two is an American.

Number Three is a Frenchwoman. Number Four, the

'Destroyer,' is an Englishman."

"A Frenchwoman, eh?" The American whistled.

"And Halliday disappeared in France. Maybe there's

something in this. What's her name?"