In the rebellious northern frontier province of colonial India, British Army Captain Scott, a young prince and the boy's governess escape by an obsolete train as they are relentlessly pursued by Muslim rebels intent on assassinating the prince.
Sir Philip Ashlow (Stewart Granger), his neglected wife, Lady Ashlow (Ava Gardner) and his best friend Henry Brittingham-Brett (David Niven) are shipwrecked on a desert island. This potential ménage à trois where the two men compete for the lady's attention is interrupted by the unexpected arrival of a fourth inhabitant of the island.
An anthology series produced by Thames Television, comprised of short mystery, suspense or crime adaptations featuring, as the title suggests, detectives who were literary contemporaries of Arthur Conan Doyle's Sherlock Holmes.