Suspense - Season 1 Episode 3 Suspicion

Everyone's in a tizzy over the arsenic poisoner who's still at large; police think the murder might be a woman. In the Thomas household, doting old George acts surprised to find his weed poison (with arsenic) under the kitchen sink. His wife, a delicate woman with bad nerves, defends their cook, a woman they hired who came with no references. George becomes suspicious of their employee and has the hot cocoa she left for him analyzed. When the results come back positive, he races home to save his wife before it's too late.