Love from Doris

The title promises Doris. The letter that sets the story going is signed Rita, which tells you the kind of episode this is: a penpal romance that is nothing of the sort. Military security intercepts the letter on its way to a lonely serviceman, and in among the warm words are casual references to secret information. Inman reads it and sends Jordan to find out who Rita really is.

Scott Forbes wrote it and John Russell directed, and the investigation fans out across the expected world of handoffs and cover stories: Drysdale, Costello, Banks, Detective Sergeant Miller, Major Carter, all of them certainties in a case where nothing is certain. Georgina Hale's Lisa keeps the human side of the business alive, and Mona Hammond's Veronica Williams suggests what the whole thing costs the people caught in it. Nobody in the cast is quite who they appear to be, which is the point of the exercise. The letter itself is the best clue, and the team reads it the way an archivist reads a document: slowly, and for what is missing.

And the show has real fun with the gap between the love letter and the operation. Rita writes like a sweetheart, all warmth and longing. Jordan reads her the way he reads a file, for what she is not saying. That gap, between affection and intent, is where the whole case lives.

Derren Nesbitt's Jordan and Fulton Mackay's Inman anchor it, with Morris Perry as Moxon, Georgina Hale as Lisa, Kevin Stoney as Drysdale, Dermot Tuohy as Costello, Ray Barron as Banks, Alister Williamson as Det. Sgt. Miller, Mona Hammond as Veronica Williams, Hugh Futcher as Cotterill and John Woodnutt as Major Carter.

A lonely soldier, a foreign penpal, and a letter that mentions the wrong things. It is a small beginning, and the episode makes it feel like the whole intelligence war in miniature.