Protection: cast, plot, and everything we know

Siobhan Finneran and Katherine Kelly star in Protection
Siobhan Finneran and Katherine Kelly star in Protection (Image credit: ITV)

Siobhan Finneran leads an impressive cast in Protection, a "suspenseful conspiracy thriller".

ITV's six-part series will delve into the murky and complex police protection programme, to find a world of maximum secrecy and false identities, where you can’t trust your own colleagues.  

Protection is based on an idea by a witness protection specialist who served in the Met for 30 years and looked after a number of high-profile cases and informants, including, war criminals, terrorists and criminals of all kinds.  

"The series is a suspenseful conspiracy thriller, but it also explores some complex moral questions, about how far we should be prepared to go in order to serve the greater good," says screenwriter Kris Mrksa. 

"The murky world of witness protection, where hardened criminals are often sheltered, in the hope that they will help bring down other criminals, provides the perfect context for examining these thorny issues. I'm incredibly excited to be working with the team at New Pictures [The Missing, Des & The Long Shadow] again, in bringing this complex world to life.”

Here's everything we know so far about Protection... 

Protection release date

Channel bosses have confirmed Protection will premiere on ITV and stream on ITVX in 2024. When we have an official premiere date, we'll let you know. 

Filming has commenced in Liverpool and Katherine Kelly shared an update from the production on Crosby Beach with her Instagram followers in late September (below). 

All3Media International has exclusive worldwide distribution rights for the series. 

Protection plot

An official synopsis reads... 

"Witness protection is often glamorised as keeping innocent witnesses safe from harm but the truth is darker, murkier, and far more complex. Many protected people are themselves criminals. It’s a life of moral compromise. It also involves maximum secrecy, false identities, and a world where you can’t trust your own colleagues.  

"Based on the first-hand experiences of a long serving witness protection officer, Protection is about what happens when the system breaks down. It’s about a police officer, Detective Inspector Liz Nyles (Siobhan Finneran), who finds herself at the heart of such a breach; personally compromised by an affair with a colleague, but determined to fight back, and uncover the true source of corruption within her unit. To redeem herself, the reputation of her lover, and to keep her witnesses safe. Even if they don’t always deserve it.  

"Navigating the morally-grey, clandestine world of witness protection, Liz’s mission to find the truth will take her deep into the heart of the criminal underbelly and beyond as she becomes more and more torn between caring for her family, her loyalty to her lover and her duty as a police officer. This is the story of a smart, tough cop, out of her depth in a world where nothing is as it seems. 

"With a deft narrative that engages from the outset, Kris Mrksa creates suspenseful twists and with every hairpin turn perfectly navigates the story to ensure the audience won’t know who to believe and who is telling the truth." 

ITV’s Head of Drama Polly Hill will oversee production on behalf of the broadcaster and is delighted to have secured a trio of top female actors... 

“The clandestine world of witness protection creates a thrilling backdrop for this intriguing crime thriller written brilliantly by Kris Mrska," she commented in an official statement. "We’ve attracted an amazing cast including Siobhan Finneran, Nadine Marshall and Katherine Kelly and I’m delighted to commission the series from Willow Grylls and her team at New Pictures.”

Protection cast

Siobhan Finneran will lead the cast as the Detective Inspector Liz Nyles. After making her name as meddlesome ladies maid Sarah O'Brien in Downton Abbey, Finneran has had parts in a string of acclaimed dramas, such as Happy Valley, Time, The Stranger and A Confession. 

She will be joined by Katherine Kelly (The Long Shadow, Liar) and Nadine Marshall (Sherwood season 2, Trigger Point), who will also take starring roles. 

Additional casting includes Barry Ward (Bad Sisters), Chaneil Kular (Sex Education), David Hayman (Sid and Nancy), Nichola Burley (The Gold) and Akiya Henry (Silent Witness).  

Is there a Protection trailer? 

Not yet, but we'll be sure to let you know when it lands. 

Sean Marland

Sean is a Senior Feature writer for TV Times, What's On TV and TV & Satellite Week, who also writes for whattowatch.com. He's been covering the world of TV for over 15 years and in that time he's been lucky enough to interview stars like Ian McKellen, Tom Hardy and Kate Winslet. His favourite shows are I'm Alan Partridge, The Wire, People Just Do Nothing and Succession and in his spare time he enjoys drinking tea, doing crosswords and watching football.