Mr Moss is described as being "tall, dark and well dressed, with a drawling voice and a superior manner".
After snatching the suitcase from Diana Harmon, Mr Moss is stopped by Police Constable Abel. He claims that it is his suitcase, and that he is a theatrical costumer, who had brought a case of theatrical properties for an amateur performance. However, the suitcase is opened to reveal some clothes, just as Diana had described. Mr Moss then gives a "magnificent" display of dismay and compunction, and apologizes for snatching the suitcase.
Inspector Craddock later explains that Mr Eccles and Mr Moss must have seen Walter St John get on a bus to Chipping Cleghorn, and must have driven ahead and waited for him there. It was Mr Eccles' revolver that was used, but Inspector Craddock suspected that it was Mr Moss who shot Walter.