Thicker Than Water

Thicker Than Water is an inheritance puzzle with a fairground at the end of it. Margery Keeverton is looking after the estate of her uncle Geoffrey, who made a lot of money from a fairground amusement arcade and has left everything to her. Staying at his house, she starts to receive nuisance telephone calls that make it clear she is being followed and refer to an unpaid debt.

Ken and Harry are asked to help. Harry rather likes Margery and is so keen that he takes a week off. Her solicitor, Peter Haymon, has little confidence in Ken's abilities, and when Harry takes Margery to the races they meet Haymon there, spoiling Harry's plans for a romantic day. A friend tells Harry that Haymon is one of the shiftiest lawyers in the Midlands.

Ken and Harry watch the house at night, and eventually a shady figure appears in the garden. They give chase, but the man gets away after giving Harry a black eye, leaving his coat behind. In the pocket Ken finds a plastic .22 bullet, the kind used in fairground shooting galleries.

At the fair he meets Pat Goran, an elderly woman who runs a shooting stall and comes from a long line of showmen. Her grandson, Ian, wants to buy into a slot-machine business. Ken challenges Ian, who admits he attacked Harry and says the house should be his, because Geoffrey Keeverton was his father. Pat tells the story: Geoffrey was married to her daughter, they separated, and he paid maintenance for Ian.

Ken suspects Margery of trying to discredit Ian to avoid sharing the estate, until she shows him notebooks listing many payments to Pat Goran, whom she assumes to be a man. Then Haymon, asked about Pat, refers to her as "her". How does he know that Pat is a woman? Ken and Harry tip him off that they are close to finding Pat, and when Haymon rushes to the fairground and threatens Ian, Ken is watching.

Ken strands him at the top of the Big Wheel and gets a confession. Once Margery had been persuaded to expand the estate, Haymon planned to introduce Ian as the rightful heir, claiming a bigger commission for restoring a bigger estate. Haymon is discredited, and Margery agrees to share the inheritance equally with Ian.

Rocky has a lesser story: two larger-than-life Northumbrian farmers, Joe and Calum Trevellyan, ask CBS to recover their sheepdog, Clara Bow, stolen at a trial. Rocky and Calum steal it back, and Rocky is caught. Calum later admits the dog he took was a champion stud he borrowed to father Clara Bow's pups.

Bernard Dempsey wrote the episode and Anthony Garner directs. Beryl Reid plays Pat, Benjamin Whitrow is Haymon, and Ciaran Madden is Margery.

The strength is the pronoun. A lawyer who knows too much because he slipped on one word is a classic detective's catch. The Big Wheel scene is a good way of delivering the confession. The weakness is the dog story, which is a short joke at the expense of the farmers' unconvincing accents.