Shows with a devoted fanbase like Luther often create the clichéd ‘water-cooler talk’ at work the next day, prompting feverish discussion. People might talk about how sinister the villain was, or the resolution of a tense face-off between criminal and copper. After this episode, I imagine discussion will be entirely focused on the murder of DS Justin Ripley. With the episode suffering an uneven opening forty minutes, the final third really kicks through the gears, racing toward an exhilarating and heart-breaking close. Deliberate or not, Ripley’s tragic death shares many parallels with that of Luther’s ex-wife Zoe back in series one. Luther runs to catch up with Ripley much in the way he did as he ran to Zoe’s aid. Upon seeing Ripley, Luther drops to the ground and lies next to his body, much as he does with Zoe. These structural beats have the same effect as before, wringing every drop of emotion out of Ripley’s murder, as do Idris Elba’s performance. It will be interesting to see how Ripley’s death affects Luther in his pursuit of Marwood in the series finale. The two had an intense encounter themselves, with Marwood holding Luther at gunpoint as they discuss the morals of Marwood’s actions. As with any one-on-one exchange involving Elba, this scene is gripping and hopefully we will see another similar encounter next week. Marwood is a far more complex criminal than many presented on Luther. Elliot Cowan’s performance does not provide the same blood-curdling chills as Kevin Fuller’s sex killer from the opening two episodes. Instead, he is genuinely unsettling as a normal man driven to the brink by the murder of his wife. That idea might be cliché (as are many in Luther) but it is handled exceptionally well. Marwood’s plight makes viewers question the legal system, but I also found myself questioning my personal views on justice itself. What punishment fits the crime of murder, or paedophilia? While the climactic minutes and villain are to be commended, the episode certainly has its flaws too. Stark and Grey’s investigation into Luther feels somewhat undercooked. After a promising start in the series opener, Stark has become a pretty uninteresting caricature rather than a fully fleshed-out character. The fact that DSI Grey is only just beginning to question Stark’s methods also completely undermines her character. She is supposed to want to root out dirty coppers, and then aligns herself with the overtly corrupt Stark to achieve her goals? It just seems a little… well, at best extremely misguided, at worst very stupid. Their harassment of Luther’s love interest Mary also leaves a bitter taste in the mouth. Mary knows neither of these people, and yet she invites them into Luther’s house, and sits with them to discuss his past. This felt like a contrived, rushed way to drive a wedge between Luther and Mary. With little-to-no character development for Stark along the way, this plotline is proving a hindrance to the main crime-solving elements of the show. Read Tom’s review of the previous episode, here. Please, if you can, buy our charity horror stories ebook, Den Of Eek!, raising money for Geeks Vs Cancer. Details here.