Is The Unforgivable a true story?

Her mission is made all the more challenging by the fact she's being pursued by the son of the man she'd shot all those years ago – and so it becomes a race against time to do something before it's too late.

That story might sound a little familiar, and so you could be wondering if the film has its roots in a real-life case – read on for everything you need to know.

Is The Unforgivable a true story?

No, the film is not based on real events. The reason that it might be familiar is actually rather more straightforward – it is adapted from a three-part ITV drama that originally aired in 2009.

That drama, which was written by Sally Wainwright and starred Suranne Jones in the Sandra Bullock role, was titled Unforgiven – and the new film has presumably been retitled in part to avoid confusion with the classic Clint Eastwood revisionist Western of the same name.

A Hollywood remake had been on the cards for a long time, with Mission: Impossible's Christopher McQuarrie and The Queen's Gambit's Scott Frank among those to have been attached to write and direct at various points during development.

In the end, the screenplay was adapted by Peter Craig, Hillary Seitz and Courtenay Miles, with German filmmaker Nora Fingscheidt in the director's chair.

It is far from the first time an acclaimed British TV series has been made into an American film – with previous examples including Paul Abbott's State of Play and Dennis Potter's The Singing Detective.

Want to know more? Here is a full list of everyone who stars in The Unforgivable cast.

The Unforgivable is streaming now on Netflix. Check out more of our Movies coverage, read our guide to the best movies on Netflix or visit our TV Guide to see what’s on tonight.