Marple: The Blue Geranium (2010)

While visiting her friend Dermot in Little Ambrose, Miss Marple is drawn into investigating the death of Eddie Seward, whom she'd met on the bus and who is found having apparently drowned in the river.Within a few days however, there is a second suspicious death, that of Mary Pritchard who seems to have died from fright. She was disliked by many and had recently caused a scene when her husband George was inaugurated as the Captain of the local golf club. Even Dermot disliked her as did her sister Philippa, who was once engaged to George, whom she described as the love of her life. Phillipa ended up marrying George's brother, Lewis Pritchard, and they are constantly having money problems. A third death - this time one of George Pritchard's former mistresses - convinces Inspector Somerset that George, who conveniently confesses, is the murderer. Miss Marple thinks otherwise and sets out to prove it.