The Blue Geranium

S5 E3: Miss Marple tries to stop a court hearing when she discovers important new evidence about the `Blue Geranium' murder case. Months before, Marple is attending a tense gathering at a village golf club when the dead body of a strange young man is discovered. Soon after, a wealthy and unpopular local woman is found dead in bed. Did she really die of shock when the geranium in her wallpaper turned blue?