"The Case for the Defence" tells the story of a case known as the "Peckham Murder", in which an old woman named Mrs. Parker has been murdered in the middle of the night by a heavyare several witnesses, the main one being Mrs. Salmon, who glimpsed Mr. Adams' face after seeing him on the steps of Mrs. Parker's house hiding a hammer. At the trial, Mrs. Salmon presents her account firmly and honestly, and is confident that the heavy man in the dock is Mr. Adams. However, she becomes flustered when the man's counsel presents to her an identical-looking man at the back of the courtroom, who is revealed to be his twin brother.