Secret of the Blackbirds

Mr. Fortescue, the head of a large corporation, dies under mysterious circumstances. The autopsy reveals he was poisoned. Despite being surrounded by family, none of them truly cared for him, and each had their own motive for murder. But who is the real culprit? And who is behind the subsequent deaths of his young servant and his wife in the following days? Naturally, the only one capable of unraveling this mystery is Ms. Marple. As always, the killer turns out to be the person you would never have suspected.