As a writer, I try to learn about the craft of writing a novel from every source I can. The obvious source is reading and I try to read all the time. Each day I’m perched on my exercise bike for an hour, devouring anything I can get my hands on, and even if I have no more time for reading that day, at least I’m getting in the literary and physical miles at the same time. My favourite novel last year without a doubt was Kamila Shamsie’s Home Fire, the retelling of the Antigone story. Shamsie is a writer who clearly knows how to craft a clever story.

But I am on a mission to learn and to improve my writing all the time, and that means seeking out all other means of refining my skills. And this brings me to the fifth series of Luther on TV, written brilliantly by Neil Cross. Now it has to be said that Luther is a terrifying programme. That shouldn’t be a problem for me: I was brought up with scary films and books. My mum loved everything from Bram Stoker’s Dracula to Agatha Christie. She loved the thrill of danger. It was escapism. (It has to be said at this point that my dad did not read, nor could he shift his stance from a stubborn belief in only that which he could see and touch at any moment of time, the real, the mundane.)

But since the screening of the Luther episode of the killer in the street wearing the luminous mask, I won’t to go out in the dark to put out the bins. Neil Cross deliberately targets our potential to be afraid and he unleashes the power that lies in our dread and anxiety about the unknown. He said ‘So all of the bad guys are avatars of my fears and anxieties, and once I have isolated that fear – the guy under the be- that’s a shared anxiety with so many of us – once I’ve got that initial spark of anxiety, then I begin to think about the character that could exemplify it… Who is he? Why is he doing what he is doing? What does he want? But that ultimately comes second to the scary stuff. You start with the fear and work backwards.’

Character is always important. Idris Elba’s John Luther is a sex symbol of our time, but more importantly he’s a maverick, a flawed genius who steps outside the rules, a man of the law who sails close to the wind, breaking convention. Other characters shine. Ruth Wilson’s Alice Morgan is brilliantly contrived – a ruthless unpredictable psychopath who turns up unexpectedly and behaves outrageously.

William Faulkner said ‘In writing, you must kill your darlings’ and Cross does exactly that in Luther. Justin Ripley’s death shocked us all, as if we thought someone so loyal, so important and good-natured was exempt from being murdered, and when he was not, we were stunned and we mourned. And then came the demise of Benny, the tech expert – another martyr. Neil Cross underpins my belief that the reader should be surprised by what happens next – no character is safe, no eventuality should be predictable. And the importance of complex likeable central characters with the potential to amaze but who bring empathy and warmth and human vulnerability is not to be overlooked.

An impactful setting is something we all strive to create in our writing. Luther is firstly a visual medium, but it works on the same principle as writing. Whether it is from a camera angle or the written word, whether we are following a victim onto a bus or watching someone take off their shoes from a killer’s viewpoint under the bed, setting can create emotional impact and needs careful consideration. Cross’ work prompts me to ask myself if I can make the setting more powerful, more relevant or can I find an alternative setting that is more surprising and unexpected.

Neil Cross excels at twists and turns in storylines and having several threads unravelling at the same time. He leaves vital questions unanswered, which draws the viewer in, and he misleads us deliberately to add to the surprise at the moment of anagnorisis. My background in both theatre and writing tells me how vital it is to suspend disbelief, to keep the interest of the audience strong but to draw them out of the comfort zone and keep them guessing. In series 5 of Luther, we wonder what will happen to George Cornelius’ kidnapped son, but we don’t expect what Alice does or when and how she’ll do it. We are interested in how new DS Catherine Halliday will fare working with Luther – the signs are mixed, a tentative novice but with a cool head. It could go horribly wrong. And DSU Martin Schenk is on to Luther – he now has real evidence of his dangerous liaison with Alice.

Then there are the murderers – Vivien Lake and her evil, strange husband, Jeremy: the luminous horror mask, the needles, the eyeballs, and that incredible moment where the patient was talked through her impending heart operation by the psychopath doctor and he slipped the shocking phrase ‘diseased whore’ into the professional dialogue, much to the patient’s – and our- revulsion and incredulity. Cross is offering a master class on suspension of disbelief, terrifying the audience, misleading them and keeping them guessing, interweaving threads of characters’ action and contrasting story lines in an intricate way so that the outcome will never be clear until the shocking moments of catharsis.

I got into Luther late, and scared myself silly by watching all the earlier series in a week. Series five is no exception – it’s horrific, brilliantly contrived, the stories unfolding expertly. Most importantly Neil Cross, like any good writer, knows how to channel and manipulate his audience’s emotions, how to create the dynamic interplay between fear and hope, relief and shock, admiration and sadness and dread. He knows how to pull us in to the plot and keep us there, how to make us take sides and invest in the characters, how to force us to feel sympathy, empathy, antipathy and to steel ourselves against a huge barrage of horror. And he knows how to keep it coming.

There is a lot to be learned about writing a novel from a television series, and in particular, from Neil Cross’ Luther. Series five was excellent, and although the action is often about male killers and female victims, I still focused on the belief that the horror was real and spent a lot of it watching through the gaps in my interwoven fingers. But, like every great novel, it leaves me sad when it’s over and waiting for more, although I’ve no idea what the next series might hold. But I’m looking forward to the superb storytelling and how it can help me to refine my own writing.