Date of Birth

"Date of Birth" opens with a dead spy in Canada and works backwards to a London au-pair. The dead man apparently never met Heidi Schneider, and yet he had been watching over her welfare from a distance for years. Craven has to find out what connects the two of them, and the answer takes him through a list of women's names that reads like a ledger. It is the kind of case where the dead tell you more than the living are willing to.

That is this series at its most appealing: the espionage stays small and human, closer to a paperwork trail than a hardware job. The trail leads through the quiet record of a man who cared about a girl he could not acknowledge. There is a melancholy to it that suits Sewell's Craven, a man used to tidying up other people's messes. Sewell does his usual solid work, with Patrick Mower's Haggerty and Paul Eddington's Strand in support, Richard Beale's Commander Glover applying pressure from above, and Susan Jameson's Detective Sgt. Mary Holmes and Paul Antrim's Detective Sgt. Maguire doing the legwork. Suzanne Roquette plays Heidi, and the part asks for a quiet wariness that she supplies. And Myrtill Nádasi doubles up as Odette Guttman and Bridget Farwater, which is a tidy bit of casting economy.

Lewis Greifer wrote it, Don Leaver directed, and the pace is patient, closer to an inquiry than a chase. Katya Wyeth's Susanne Brodl and Amanda Knott's Sylvie Roche round out the cast, and the episode is the better for not rushing any of it. The questions are allowed to stay open until the right moment, and the answer, when it comes, is small and human rather than geopolitical. It is a story about a connection that never got to be a life.

The reveal lands quietly. Some episodes of this series shout; this one just points.