They may never come at all, and in that case I shall not come back at all.

Or they may come only at the very end and after many years.

Therefore I thought that I would like just one person to know the truth thoroughly in case I do not come back.

If you hear definitely that I never can come back, I would be glad if you would tell my father." "I understand," said Sutch.
"But don't tell him everything--I mean, not the last part, not what I have just said about Ethne and my chief motive, for I do not think that he would understand.

Otherwise you will keep silence altogether.
Promise!" Lieutenant Sutch promised, but with an absent face, and Feversham consequently insisted.
"You will breathe no word of this to man or woman, however hard you may be pressed, except to my father under the circumstances which I have explained," said Feversham.
Lieutenant Sutch promised a second time and without an instant's hesitation.