“One can only be thankful poor Harriet knew nothing about it,” remarked Mrs Matthews in a saintly voice.
“For God's sake don't talk as though she were a sheep being driven to the slaughter-house!” exclaimed Stella, quite pale with disgust.
“Stella dear, you forget yourself,” said Mrs Matthews repressively. She transferred her attention to the Superintendent. “One is terribly shocked, of course, but what my son says is right. This appalling thing may have been done at any time.”
“But not, Mrs Matthews, by any person,” replied Hannasyde.
She spread out her hands. “Anyone who was familiar with this house could have found the opportunity to do it, Superintendent.”
“Possibly,” agreed Hannasyde. “But few people can have had any motive for killing Miss Matthews.”
Guy muttered: “O God, we're just where we were before!”
“Ah, Superintendent,” said Mrs Matthews, sadly shaking her head. “What, after all, do we know of each other's lives? Even I who was so close to my poor sister-in-law would hesitate to say that she had no enemies of whom I knew nothing. She was a strange, eccentric woman! I have sometimes wondered whether there might not have been something in the past to account for many of her oddities. So often an apparently warped nature —”
“If you, who were so close to her, do not know of anything sinister in her past, I think we may assume that there was nothing,” interrupted Hannasyde, with an inflection of contempt in his voice. “The discovery of the medium through which the poison was administered has not enlarged the field of suspects, as a moment's reflection will, I think, show you.”
Stella grasped a chairback, and said desperately: “But not one of us three had a motive for killing Aunt Harriet! Not a real motive! This is like a nightmare! Things don't happen like this! Leave me alone, mother: I won't be quiet!” She shook off her mother's hand, laid warningly on her arm, and said, trembling: “I don't pretend to know who did it. Perhaps she knew something that—that made her dangerous. Supposing it were something about that man you're looking for—the one who disappeared?”