Falling Darkness

Halloween night in Oxford, and Dr Hobson's professional life collides with something from her past. A university friend of hers is found dead, staked through the heart, a garlic bulb placed in her mouth. The staging is theatrical and nasty, and the case does not stay at arm's length for long. A medium approaches Lewis and Hathaway with a warning that they are in grave danger, which the detectives take with the professional scepticism it deserves, until the bodies start proving her right.

The following day a student is murdered in the house Hobson shared with her university friends, and a clue at the scene points towards a third victim. As the body count climbs, the focus inevitably swings back to Hobson herself. Lewis and Hathaway are forced to confront the uncomfortable possibility that she knows more about these deaths than she is letting on, and the episode does not spare her the suspicion.

But the vampire trappings are handled with a straight face, which is the right call: the murders are staged to frighten, and the staging works on the characters long before the detectives see through it. Hobson's friends become a cast of suspects, and the shared house grows colder with every body.

Colin Dexter and Russell Lewis wrote it, and Nicholas Renton directed. Niamh Cusack plays Dr Ellen Jacoby, Lucy Griffiths is Madeleine Escher, Brodie Ross plays Roddy Allen, Lauren O'Neil takes Rowena Trevanion, Louise Hunt plays Professor Ligeia Willard, John Sessions is Professor Rufus Strickfaden, Adam Levy plays Dr Nicolae Belisarius and Alex Price takes Victor Clerval. Clare Holman, Kevin Whately and Laurence Fox carry the centre of it.

The domestic setting is the key to the episode's tension. A shared house full of clever people becomes a claustrophobic trap, and the murders keep coming closer to the regulars. There is a genuine chill in watching a character you like become a suspect in her own story, and the show handles it with care.