Note: This article contains spoilers for Luther series 5
Ask a fan of the BBC's grisly crime thriller Luther what they love about the show and the answer in all likelihood will consist of one or both of these two things: Idris Elba in a delightfully gothic London setting, pursuing deranged serial killers, and/or his character DCI John Luther's twisted relationship with the unhinged Alice Morgan (Ruth Wilson).
The series' previous outing, a limp two-parter in 2015, was sorely lacking the latter ingredient – Wilson's commitment to US series The Affair meant that she was unable to reprise her role, with writer/creator Neil Cross opting to dispatch Alice off-screen.
Luther aficionados weren't impressed, and neither was Wilson. "I watched it and was like, 'She's not dead... she can't be dead'," the actress would later recall. "You can't kill her and not see it, right?"
By early 2018, her schedule had opened up and Wilson was able to return to filming on Luther, with her character's demise implausibly reversed.
But even though Alice was back, the show couldn't quite course correct in its fifth series – as if to compensate for her former absence, Cross doubled down on Alice's presence for this new four-parter, with John's psycho ex-lover dragging him into a violent feud with gangster George Cornelius (Patrick Malahide).
The chemistry between Wilson and Elba was as electric as ever, and having Alice back certainly emphasised how profoundly the show suffers without her in it. But it's possible to have too much of a good thing, and by focusing so heavily on John's personal crises – his troubled dynamic with Alice, and how it led to much bloodshed as the war with Cornelius escalated – Luther again grew lop-sided.
Only lip service was paid to the story of a psychotic surgeon (Enzo Cilenti) preying on the Big Smoke's unsuspecting, and the petrifying partner-in-crime (Hermione Norris) who enabled him. Previously, this sort of thing would've been Luther's bread-and-butter – the nasties lurking under our beds, outside our houses, in the backseats of our automobiles...
But while Cilenti and Norris both gave bravura performances, this latest serial killer plot – for all its memorable moments featuring night buses and wheelie suitcases – felt very much like an afterthought, for both writer Cross and his lead character.
Luther spent practically no time at all actually investigating the murders perpetrated by Cilenti's character Jeremy Lake. Instead, the lion's share of the detective work - including the exposure of original suspect James Hauser (Jami Reid-Quarrell) as a patsy, set up by Lake and wife Vivien - was carried out by Wunmi Mosaku's chipper DS Catherine Halliday, who received a bullet to the head for her efforts.
The concluding episode saw DCI John arrive on the scene just in time for his 'Hero Moment', pinning the runaway Lake to the ground and pummelling him mercilessly, having barely poked his nose into the investigation up until that point.
Now, this is Luther – we're not expecting interminable scenes of Elba deliberately filling out paperwork. But the lead character's failure to carry out anything even remotely resembling police work this series was almost comic – once or twice each episode, we'd be served an awkward scene where John telephoned Catherine to excuse his absence from the station, during which she'd relay her latest investigative breakthrough.
The best of Luther struck a compelling balance between the man's job and his personal life, also exploring how the two often intermingled in unexpected and dangerous ways. Here though, the series seemed most concerned with making up for lost time and digging deep into John and Alice's unhealthy bond (which might not have been such a problem if the latter's reappearance hadn't been so thoroughly tied to the uninspiring Cornelius storyline).
What this latest series was about, more than anything, was how a conflicted man's loyalties – John's loyalty to Michael Smiley's tragic Benny, his foolish but unshakeable desire to protect Alice – led to his downfall, with the final scenes showing him defeated, led away in handcuffs by heartbroken boss Schenk (Dermot Crowley).
Which is fine, but for most fans, that's not really what Luther is all about. A big part of the thrill really is in the chase. So if that much-vaunted movie version does ever surface, here's hoping Neil Cross, Elba and company remember that a hero is only as good as his villains.
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