After last week’s head scratcher of a whodunit, Endeavour takes an entirely different direction with ‘Nocturne’, developing an oddly gothic tone as the team investigate the murder of a man in a museum and a seemingly unconnected ghost story at a girls’ boarding school, where soon after, the girls start going missing.

Visually this episode is a joy to watch, with the macabre tones fitting in with the darker themes of the episode, yet remaining tonally very different to what Endeavour has done before. The story has a vein of the supernatural running through it and, while this is eventually dismissed, it initially gives the story a breath of life and originality, but without ever verging on gothic horror parody.

Once again, I was impressed by the complexity of the story, and how it demanded the viewer pay attention to detail. Almost everything made sense in the end, and despite a few red herrings and an overly complicated final act explanation that ties the murder, the disappearances and the eventual resolution together, the story made relative sense.

Technically, it’s a very well-crafted episode. Scribe Russell Lewis continues to maintain the balance in Endeavour Morse’s character, with notions like his lack of football awareness, his blossoming desire for the ladies and his continued appreciation for the outsider, who he identifies with.

Director Guiseppe Capotondi (La Doppia Ora) adds a stylish flair to proceedings with notable direction. Capotondi has a background in music video and advert direction and this is reflected here, in shots like the tense yet stylish opening sequences of bloody images and the austere grandness of the boarding school scenes.

Shaun Evans interpretation of Morse feels more bedded in this series and he is impressive in his subtle complexity in this episode.

There is also a bit of development here as he shows an interest in his neighbour Monica (Shvorne Marks), his chat about ladies and life with Thursdays daughter Joan (Sara Vickers) and finds more respect from his colleagues as this case progresses.

Roger Allam, as Thursday, continues to compel, and the relationship between him and Evans makes for a very believable and watchable partnership. Endeavour’s casting has always been spot on, even including the inclusion of John Thaw’s real-life daughter Abigail as reporter Dorothea Frazil. To see this as purely nepotism is a dis-service to Thaw, who has a grounding and contained performance, but also helps maintain a familial connection that resonates in the production.

Of course, there are some flaws. The languid pace of events is still an issue in the show’s storytelling and there is often a sense of the show trying to be too smart for its own good with its Latin and literary references. Once again, secondary characters and plot threads are also unnecessary or not entirely developed, which seems a shame.

For the most part though, ‘Nocturne’ is a gripping and engaging piece of crime drama. The ability to shift tone like this and still be credible is a good sign for the long-term future of the show.

Aired at 8pm on Sunday 6 April 2014 on ITV.

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