“On Monday Mrs. Inglethorp will take the last dose of her medicine. On Monday, therefore, at six o’clock, Alfred Inglethorp arranges to be seen by a number of people at a spot far removed from the village. Miss Howard has previously made up a cock-and-bull story about him and Mrs. Raikes to account for his holding his tongue afterwards. At six o’clock, Miss Howard, disguised as Alfred Inglethorp, enters the chemist’s shop, with her story about a dog, obtains the strychnine, and writes the name of Alfred Inglethorp in John’s handwriting, which she had previously studied carefully.
“But, as it will never do if John, too, can prove an alibi, she writes him an anonymous note—still copying his handwriting—which takes him to a remote spot where it is exceedingly unlikely that anyone will see him.
“So far, all goes well. Miss Howard goes back to Middlingham. Alfred Inglethorp returns to Styles. There is nothing that can compromise him in any way, since it is Miss Howard who has the strychnine, which, after all, is only wanted as a blind to throw suspicion on John Cavendish.
“But now a hitch occurs. Mrs. Inglethorp does not take her medicine that night. The broken bell, Cynthia’s absence—arranged by Inglethorp through his wife—all these are wasted. And then—he makes his slip.
“ Mrs. Inglethorp is out, and he sits down to write to his accomplice, who, he fears, may be in a panic at the nonsuccess of their plan. It is probable that Mrs. Inglethorp returned earlier than he expected. Caught in the act, and somewhat flurried he hastily shuts and locks his desk. He fears that if he remains in the room he may have to open it again, and that Mrs. Inglethorp might catch sight of the letter before he could snatch it up. So he goes out and walks in the woods, little dreaming that Mrs. Inglethorp will open his desk, and discover the incriminating document.
“But this, as we know, is what happened. Mrs. Inglethorp reads it, and becomes aware of the perfidy of her husband and Evelyn Howard,