Renegade cop John Luther’s transition from TV to film is, like the man himself, flawed but likeable.

Fallen Sun, (in cinemas now, on Netflix from March 10) is the first in a planned series of feature-length cases for the Cockney Detective Chief Inspector played by Idris Elba.

As is often the case with TV-to-movie spin-offs, this extended episode is bigger, louder and a whole lot dafter than anything we saw on the small screen.

It begins with a brazen re-jigging of the final episode. In 2019, we saw Luther finally led to jail by his wonky moral compass. Here, his downfall was the work of a murderous computer hacker called David Robey ( Andy Serkis ).

Idris Elba at the premiere of Luther: The Fallen Sun
Idris Elba at the premiere of Luther: The Fallen Sun
Co-star Cynthia Erivo plays Det Supt Odette Raine in the movie
Co-star Cynthia Erivo plays Det Supt Odette Raine in the movie

As part of a confusing scheme to build an evil online network, Robey had kidnapped a young London cleaner.

To stop the maverick cop from feeling his collar, Robey leaked information about Luther’s crimes, from tampering with evidence to witness intimidation.

In a scene that didn’t feature in the BBC series, Luther vowed to the missing cleaner’s mum he would find her son.

To keep his promise, he busts out of prison to hunt down Robey and forge an uneasy alliance with his replacement, Det Supt Odette Raine (Cynthia Erivo).

The prison-break sequence is an early reminder that Netflix producers have bigger budgets than those working for the British public broadcaster.

Luther engineers an unlikely prison riot, before scrapping his way through scores of lags who are desperate to enact revenge on London’s most infamous detective.

Once he’s reunited with his trademark wool overcoat, we see the vigilante perched on the top of a London tower block surveying the crime-ridden city like a herringbone Batman.

Andy Serkis plays villain David Robey in the crime drama
Andy Serkis plays villain David Robey in the crime drama

If that sounds a bit ridiculous, wait until you get a proper look at Andy Serkis’s barnet. Saddled with the type of luxurious bouffant previously only seen in faded barber shop photos, Serkis struggles to convey the requisite level of menace.

He can only manage ridiculous or mildly creepy, neither of which work for a serial killer with an icy Norwegian lair.

Still, somehow, Idris Elba holds it all together.

Exuding the brooding charisma that made the BBC series so watchable, his detective is still a thoroughly compelling anti-hero.

The ending tees up a new role for Luther in the next film.

Hopefully, it will have fewer plot holes and a much scarier villain.