smoky and the tramp could not have overheard the conversation he did. "Wasps' Nest" Sitting on the garden terrace of his large house on a summer evening, John Harrison is delighted to receive an unexpected visit from Hercule Poirot. The detective tells him that he is in the locality to investigate a murder but amazes Harrison by admitting that the murder has not yet been committed but that it is better to prevent one happening first. He then cryptically turns the conversation round to a wasps' nest on a tree that he sees nearby and Poirot and Harrison discuss the destruction of it. A friend of Harrison, Claude Langton, is going to handle the task for him using petrol injected by a garden syringe but Poirot tells him that earlier that day he saw the poison book in a local chemist's and an earlier entry made by Langton for the purchase of cyanide, despite Langton having told Harrison that such substances should not ever be available for pest control. Poirot asks a quiet question: "Do you like Langton?" and they talk of Harrison's engagement to a girl called Molly Deane who was previously engaged to Langton. As they discuss Langton's disposition towards Harrison, Poirot's meaning becomes quite clear to the other man – he is being warned. Poirot asks when Langton is returning and is told nine o'clock that evening. Poirot tells him that he will return at that time, wondering as he goes if he should have waited behind. Poirot returns just before the appointed time to find Langton leaving, the nest still intact. Harrison seems to be fine and Poirot hopes that he is not feeling any ill-effects of having digested the harmless washing soda that he consumed. Harrison is surprised. Poirot tells him that he traded the cyanide Harrison had in his pocket for the soda when he visited earlier on. Poirot met Langton after leaving the chemist's and heard from him that Harrison had insisted on the use of cyanide over petrol. Poirot witnessed the early signs of Langton's romance with Molly Deane being rekindled and Harrison leaving a Harley Street consultant having obviously been given bad news. Harrison confirms that he has two months to live. Having seen signs of Harrison's hatred for Langton, Poirot surmised that Harrison was planning to commit suicide and make it appear that Langton had killed him, ensuring that his