Black Museum is a radio crime drama with an unusual organising principle: each story is built around an exhibit, not an investigator. Every case is attached to an object said to be kept at Scotland Yard, in the collection that gives the series its name. Orson Welles speaks the framing passages from London. He calls the stone building on the Thames that houses Scotland Yard 'a warehouse of homicide' and runs through its contents like an inventory: a flower pot, a coffee cup, a curtain rod, a tallow candle, a mounted cat. Then he picks one up. A shilling gets the full treatment, down to its silver alloy and milled edge, before the drama explains why it matters. What follows is mostly staged dialogue. The narrator steps in to skip ahead, set a scene or point out the clue a listener should hold on to. The settings change from case to case. An inspector questions a club singer about a lucky coin and about who came calling on other nights. On a ship that has left Cape Town, a captain calls a doctor to a first-class cabin. There, a stewardess had found the porthole swinging open and the sheet marked with what may be lipstick and blood. Police print sketched postcards found hidden at the back of a bureau, betting that someone will know the drawings. A man takes a pistol from a soldier's holster, and the narrator notes that a lanyard might have saved two innocent lives. Medicine is a frequent turning point. One doctor refuses to sign a death certificate until he has done the post-mortem himself. In another household, constant retching is named as the prime symptom of arsenical poisoning, and a wife has been soaking flypaper for what she calls a complexion preparation. The questioning is clipped; the narration in between is grave and unhurried. The outcomes are not always tidy. One case closes on a jury finding the accused not guilty, and the postcard at its centre, with its rising sun, still unexplained. Another follows a conviction to a life spent in Dartmoor Prison and notes that the House of Commons suspended the death penalty just afterward. Whatever the verdict, the story ends by returning the object to its place in the museum. That return is the payoff: something first heard as one item in a list comes back at the end with a whole case file behind it. The shilling case shows the whole frame, from the opening inventory to the final return to the exhibit.