Allegory of Love

Marina Hartner is killed with an antique Persian mirror, which is already an unusual way to go. Beside the body the police find a bloody scrap of paper bearing a single strange word: Uqbara. Lewis has no idea what it means, but he has a suspicion about who might. The answer seems to lead to a fabulously successful Oxford-based fantasy novelist, whose professional luck looks suspiciously like inside knowledge.

From there the case goes somewhere surprisingly modern. The investigation pulls Lewis through a dating site, of all places, and into the lives of people who orbited Marina without ever quite knowing her. Dorian Crane, Melanie Harding, Alice Wishart, Hayden Wishart: each interview adds a layer to the puzzle without solving it. It is a mystery built out of small details, the word on the paper, the mirror, the online trail, and the show trusts the viewer to keep up.

But the word Uqbara does a lot of work as a mystery object, the kind of clue that means nothing until it means everything. The show enjoys withholding it, and the dating site detour keeps the investigation feeling contemporary rather than academic. This is a puzzle with a modern heartbeat.

Colin Dexter, David Pirie and Stephen Churchett wrote it, and Bill Anderson directed. Katia Winter plays Marina Hartner, Tom Mison is Dorian Crane, Louise Dylan plays Melanie Harding, Cara Horgan takes Alice Wishart, Olly Alexander plays Hayden Wishart, Art Malik is Professor Hamid Jassim, James Fox plays Professor Norman Deering and Anastasia Hille takes Ginny Harris. Rebecca Front's Chief Superintendent Innocent looks on as Kevin Whately's Lewis does the legwork.

The fantasy novelist angle gives the episode a sly edge, a professional storyteller being outwritten by real events. The murder is solved in the end, as it should be, but the pleasure is in watching Lewis treat a scrap of paper and a mirror as seriously as any witness. Sometimes the smallest details are the whole case.