When an old family friend and her young son turn to Miss Marple for assistance, she finds them work and lodging at nearby Greenshaw's Folly, the family home of an eccentric botanist. All seems well, until the house's loyal butler dies unexpectedly. When another houseguest goes missing, Miss Marple begins a search for the truth, unveiling secrets of both the past and present. Fiona Shaw (Harry Potter) guest stars.