Twenty short stories gather the entire short-fiction career of Jane Marple, the elderly amateur sleuth of St. Mary Mead, into a single volume. The first thirteen, originally published as The Thirteen Problems, unfold as a parlour game: a small circle of friends, including a retired Scotland Yard commissioner, a novelist, an artist, a clergyman and a solicitor, take turns recounting a real but unsolved puzzle, and the others try to name the answer before the quiet spinster knitting in the corner does. Each problem turns on a small domestic detail, and Marple's solutions draw on a lifetime of watching village human nature rather than on forensic science. The remaining seven stories, drawn from later collections such as The Adventure of the Christmas Pudding and Miss Marple's Final Cases, place her in fuller standalone cases: a body found in a vestry, a missing inheritance, a poisoning dismissed as natural death, a household with one servant too many. Across the set Marple is consistently underestimated for her age and manner, and consistently right, matching each crime to a parallel she once observed among ordinary neighbours. The collection works as the complete short-form counterpart to the twelve Marple novels, tracing the character from her 1920s magazine debut through her later cases while keeping the puzzle, not the violence, at the centre of every story.