When a sickly Victorian woman dies suddenly, a postmortem reveals that her body contains a fatal dose of arsenic. Suspicion falls on her husband and her companion, who are lovers. Inspector Martin of Scotland Yard solves the mystery of her death... over a cup of tea.
David Farrar
as Gregory Black
Geraldine Fitzgerald
as Elizabeth Grahame
Roland Culver
as Inspector Martin
Jean Cadell
as Ellen
Mary Merrall
as Lady Southdale
Harcourt Williams
as Dr. Septimus Prendergast
Charles Heslop
as Vicar
Ronald Adam
as Head-Master
Sidney Monckton
as Horace (uncredited)
