Making the jump from TV to film, even if you have a hugely popular show to begin with, is never easy. People are used to episodes, a story that plays out in chapters. The transition to the big screen doesn't always work.

After five seasons and a four-year break, Neil Cross' dark crime thriller Luther has made a go at this tricky jump with the feature length Luther: The Fallen Sun, a two-hour plus movie that picks up from where Season 5 left off.

Given that Luther occasionally linked two episodes together into a single story, I was hopeful a movie version would feel like a natural enough extension of the TV show. I was half right. The Fallen Sun sticks the landing but only just, offering an entertaining and well-acted story that can't help get tangled up in itself.

What's Luther: The Fallen Sun about?

After a long stretch of getting the bad guy at pretty much any cost, Detective John Luther (Idris Elba) finally finds himself breaking one rule too many. He starts off The Fallen Sun heading to a prison cell, leaving sadistic cyber blackmailer/serial killer David Robey (a very disturbing Andy Serkis) free to carry on doing unpleasant criminal stuff around London while he's locked away.

The good news? Luther is not about to let some measly prison bars and half the Metropolitan Police Force stand in his way of catching a bad guy, so he quickly breaks out of prison and gives chase. What follows is a dark, hectic cat (and cat) and mouse game where Luther attempts to track down Robey while the police are on the disgraced detective's own heels.

Luther: The Fallen Sun feels like a James Bond audition.

If that plot sounds a little bit ridiculous to you, then you haven't seen anything yet. Luther always had the feel of a dark graphic novel but The Fallen Sun kicks this into overdrive, with Luther standing on the rooftops of London Batman-style while Robey sets off a series of increasingly inventive (read: impossible) crimes that would probably make the Joker jealous.

The plot is more than a bit silly and Robey feels closer to a Bond supervillain than to the serial killers Luther stalked in the TV show. Fortunately Serkis is brilliant in the role, managing to appear sinister and unpleasant even while he's orchestrating his more far-fetched schemes. Elba is as excellent as ever as the grizzled Luther, proving beyond any doubt that he'd make an awesome 007 as he punches his way through prisoners, prison guards, criminals, and police officers alike, all while Luther's version of M (Martin Schenk, played by David Crowley) looks on with familiar wry disapproval. When he's not fighting multiple people at once, Luther can be found casually strolling the streets of London without any disguise whatsoever, wandering through crowded markets and popping into bars as if he isn't a wanted fugitive whose face is plastered all over the rolling news.

Like I said, it's all a bit silly. But the film almost relishes in this, and it gets away with it.

Luther: The Fallen Sun is a bit of a genre muddle.

Unfortunately, The Fallen Sun doesn't get away with everything. If the film feels like a Bond or Batman-style adventure in parts, this is mixed awkwardly with its darker crime roots. Luther the TV show always relished in a kind of claustrophobic dread and gore that felt closer to the likes of Se7en. The movie has this too — bordering uncomfortably on torture porn in some places — and it makes for a strange mixture. The tone is muddled, with the end result feeling like not quite one thing or the other. People who want the graphic novel-style adventure might be put off by the gruesome nature of the violence, while people who want the creeping dread of the original Luther might not like the big action set pieces.

In this way, and like its protagonist, The Fallen Sun risks itself by trying to do too much at once. The good bits are good enough to make us forgive the worst of its sins, but the end result is still a way off the original Luther — and a long way from perfect.

Luther: The Fallen Sun is in select theatres from Feb. 24, and streaming globally on Netflix from March 10.