The Key - Miss Silver, Bk 8 Author:Patricia Wentworth Michael Harsch's long years of work were nearly at an end. The following day he was looking forward to handing over his precious formula to the government. But the next morning he was in no fit state to hand over the formula -- he was dead. It looked like suicide, but Miss Silver knew it was murder.
As always, watch out for Wentworth's red herrings. Toward the very end of the book, a key clue was revealed. This clue was mentioned much earlier and, while I paid some attention to it then, I simply cannot believe I let it get past me.