Protection on ITV1 is THE thriller to watch this month, not least because of its epic cast of respected actors including Siobhan Finneran, Katherine Kelly, and Nadine Marshall.

They don't generally appear in duds, so you're safe with this crime drama, written by White House Farm's Kris Mrksa.

In the six-parter, we meet DI Liz Nyles, who works in the secretive and high-stakes world of Witness Protection.

One morning, a devastating incident at work raises grave questions about the integrity of Liz's unit, which is rocked with accusations of corruption... If you liked Line of Duty, you'll probably love this, too!

Here's everything you need to know about the cast of Protection on ITV1 and ITVX.

Protection on ITV cast: Siobhan Finneran stars as DI Liz Nyles

Lancashire-born Siobhan Finneran, 60, portrays DI Liz Nyles in Protection. When a family under witness protection are murdered and their only daughter survives, the single mum must find who revealed their identity...

Siobhan is famous for playing Catherine Cawood's sister Clare Cartwright in Happy Valley. She played the recovering heroin addict in all three series, which ran from 2014 to 2023.

She's also well known for playing Sarah O'Brien in Downton Abbey, and Janice Garvey in Benidorm.

Siobhan is undoubtedly one of the most bankable British TV stars on our screens, known for appearing in heavyweight dramas including BBC One's Time, The Reckoning, and The Moorside.

Her very first TV appearance was in 1987, when she was just 21 years of age. She played schoolgirl Rita, who had a passionate affair with an older man in the saucy flick Rita, Sue and Bob Too. Coincidentally, both Siobhan and her co-star George Costigan - who played Bob - later went on to star in Happy valley together.

Siobhan's next big role was playing Josie Phillips in Coronation Street. She appeared in the ITV soap from 1989 to 1990. Josie was a packer at Baldwin's Casuals.

Between 1991 and 1992, Siobhan played Milly Bates in the comedy Motormouth, before going on to win another high profile soap role. She portrayed Heather Hutchinson in Emmerdale in 1998. Her then-husband Mark Jordon was also an actor in the ITV soap. He played Daz Spencer.

Other notable roles include playing Julie O'Neill in Clocking Off, Sister Ruth in Apparitions, Mandy in The Syndicate, and Izzie Ingram in Unforgiven opposite Suranne Jones.

Later roles include Nikki Kirkbright in Cold Feet, Elaine Pickford in A Confession, Johanna Griffin in Netflix's Harlan Coben thriller The Stranger, Lin in Alma's Not Normal, and Marilyn in The Other One.

More recently, she played Marie-Louise, a prison chaplain, in series 1 and series 2 of hard-hitting prison drama Time. She also played Beryl in the horrifying Jimmy Savile drama The Reckoning.

Katherine Kelly portrays DCI Hannah Wheatley

Yorkshire-born Katherine Kelly, 45, stars as DCI Hannah Wheatley in the cast of Protection on ITV. The character is the head of the Major Investigations Team.

Of course, TV fans will know the popular actress from Coronation Street, Innocent, and the recent Mr Bates vs The Post Office.

She exploded on to our TV screens as Becky Granger in ITV soap Corrie, a role she played from 2006 to 2012. Katherine HAD starred in other shows before - like Silent Witness, The Royal, No Angels and Life on Mars - but it was her role as larger-than-life Becky that really helped catapult her to fame.

After leaving Corrie fans gutted when she left in 2012, Katherine went on to play Maloney in brilliant political crime drama The Fields of Blood. She also starred in The Guilty as Claire Reid, and played Mrs Webb in The Secret River.

We've come to love Katherine for her roles in gritty dramas, including Sally Wright in Innocent, Natalie Hobbs in Criminal: UK, DI Karen Renton in Liar, and Jodie Shackleton in Happy Valley.

She's also played Elizabeth Sutherland in Gentleman Jack, Leah in Cheat, and Lady Mae in Mr Selfridge.

Katherine starred as the Permanent Secretary in the acclaimed 2016 drama The Night Manager, and played Jane Lowry in Strike Back a year later.

The actress is also pretty convincing in comedies, too… She's played George in Bloods, Kirsty in Black Ops, boss from hell Vicky in Ruby Speaking, and Lynne in Inside No 9.

More recently, actress Katherine has taken on a number of tough, hard-hitting roles. She starred as Peter Sutcliffe's second victim Emily Jackson in The Long Shadow, and Angela Van Den Bogerd in Mr Bates vs. The Post Office.

Earlier this year, Katherine portrayed the prime suspect's psychotherapist, Dr Sophia Craven, in the cast of The Crow Girl.

Protection on ITV cast: Nadine Marshall plays DCI Amanda Kelman

London-born actress Nadine Marshall, 53, stars as DCI Amanda Kelman in the new ITV thriller. Amanda is a senior officer in the Professional Standards Department, which investigates corruption in the police.

And it's not the first time actress Nadine has played a copper on screen. In 2024, she appeared as DI Torres in Silent Witness, a role she'd previously played the year before.

Viewers will recognise actress Nadine from several high profile TV roles. She played Jenny Harris in the cast of the brilliant BBC drama Sherwood in 2022. She appeared an as old flame of DI Salisbury.

Trigger Point fans will know Nadine as DSU Marianne Hamilton in the explosive thriller. She also played Alicia Cobden in Time series 1, Jesse in Small Axe, and Christine in The Innocents. She played another cop, this time DS Shola O'Halloran, in the gritty Suranne Jones drama Save Me.

Nadine has also appeared in National Treasure, Old Jack's Boat, and Waterloo Road, among other roles. More recently, she portrayed Aria Champion in Champion, and Kim's mum Linda in Liaison.

Her film roles include Cedella Malcolm in the 2024 biopic Bob Marley: One Love, Kelly in A Street Cat Named Bob, and Miss Hammond in the Stephen Graham drama Yardie.

Barry Ward stars as DC Paul Brandice

Dublin-born actor Barry Ward, 44, stars as DC Paul Brandice in the cast of Protection. The newest recruit to the witness protection unit, Brandice is something of an unknown quantity. He's also having a passionate affair with DI Liz Nyles.

Fans of Bad Sisters will know him best as the morally ambiguous Fergal Loftus, who prefers golfing to solving crimes - which is probably for the best if you're a Garvey sister.

He's been in some seriously good dramas over his 30-year career. He played Dr Spencer in the brilliant Jamie Dornan thriller The Fall, Charlie Hall in the AI drama The Capture opposite Strike's Holliday Grainger, DI Steve McCusker in Des, and Barry McGory in Sky's Save Me. That's enough kudos to last a lifetime!

He started his acting career in 1994, playing John Paul Spencer in the Irish mini-series Family, before going on to portray Fionn Mulligan in Plotlands, Ashley Harris in Silent Witness, Jimmy Murphy in Psych Ward, and Arthur Mahon in Rebellion.

Other notable roles include Leslie in The End of the F***ing World, Matt in Taken Down, Sawyer in Britannia, and Mike Collins in White Lines. More recently, he's played Thomas Cromwell in Anne Boleyn, and Jason Mohan in Clean Sweep.

Barry's multiple film roles include Martin Martin in the comedy Extra Ordinary, Jimmy in Jimmy's Hall, and Joe Ruttledge in That They May Face the Rising Sun.

Chaneil Kular stars as DS Raj Kholi

Brummie Chaneil Kular, 25, stars as DS Raj Kholi in Protection. Liz's partner in the protection unit, he's a loyal and diligent detective.

Chaneil is a relative newcomer to the small screen, compared to some of his co-stars. His very first TV role was in 2018, when he played Tariq Amiri in the cast of Doctors.

Chaneil went on to portray Dilip Rai in Black Narcissus, the adaptation of the 1939 novel by Rumer Godden. Other notable roles include Cammy in Atlanta, Syed Tahir in Bodies, and Manish in The Cleaner.

He is arguably most famous for his leading role in the 2023 film Accused. A thinking-man's thriller, he played Harri, a young man wrongfully accused of a crime he did not commit. He must survive a long night as the online witch-hunt arrives at his front door.

Protection on ITV cast: David Hayman plays Sid Nyles

Glasgow-born David Hayman, 77, plays Sid Nyles in the witness protection thriller. Sid is Liz's dad and a former DCI in both Lancashire and Liverpool, and something of a legend in the police.

David has an extensive career spanning nearly 60 years. Film fans might know him best as Pavel from the award-winning film The Boy in the Striped Pyjamas, or Malcolm in the 1986 movie Sid and Nancy. David has actually been in dozens of films, including Heavenly Pursuits, Rob Roy, Twin Town, and Fisherman's Friends and its sequel.

During his early TV career, he's played Arnold Ryerson in Fame Is the Spur, Joe Borrow in Fell Tiger, McDade in Finney, and Henry Pulis in Blackout.

In 2017, David portrayed Brace, one of the pivotal characters in Tom Hardy drama Taboo. He went on to play William Wycherley in true crime Landscapers, Older Lenny in The Walk-In, and Andrew Brody in Chemistry of Death.

However, David is probably known for playing DCS Michael Walker in Trial and Retribution - a role he played from 1997 to 2009 - Souter in BBC One's The Nest, and Jonas Franks in The Paradise.

Nichola Burley portrays Gemma Brandice

Leeds-born Nichola Burley, 38, portrays Paul Brandice's wife Gemma in the cast of Protection.

She's probably best known for playing Donna in Goldplated, and Cathy McAleer in Drop Dead Gorgeous.

She's been on our screens since 2005 when she portrayed Michelle in the film Love + Hate. Other notable roles include Savanna Ford in thriller The Fixer, Whitney Whiteburn in Candy Cabs, Bethany in The Syndicate, and Louisa Bidwell in Death Comes to Pemberley.

Nichola also played Sophie in the twisty Netflix thriller Behind Her Eyes. More recently, the actress starred as Brenda Noye in The Gold, and played Brenda Noye in BBC drama Virdee.

Catherine Tyldesley stars as Helen McLennan

Manchester-born actress Catherine Tyldesley, 41, stars as Jimmy's wife Helen McLennan in the cast of Protection.

Coronation Street fans will know her best as barmaid Eva Price, a role she played from 2011 to 2018. And, if rumours are true, she's set to return in 2025.

More recently, Catherine has portrayed fiercely ambitious First Officer Kate Woods in The Good Ship Murder.

Co-stars Catherine and Shayne Ward starred opposite each other as Aidan Connor and Eva Price in Corrie, too, where they suffered a doomed love affair. Eva and Aidan were engaged, until she discovered he'd been unfaithful with Maria Connor. Although they did subsequently turn up for their wedding day, dramatic revelations and a fight in a water fountain meant they didn't actually tie the knot.

After leaving the ITV soap, Catherine appeared in the ITV thriller Viewpoint, as well as 15 Days, and Scarborough. Other notable roles include Emma in Trollied, Abi Peterson in Emmerdale, and Psycho Sarah in Scallywagga.

Ace Bhatti portrays DCI Arun Kapoor in the cast of Protection

Nottingham-born actor Ace Bhatti, 55, portrays DCI Arun Kapoor, head of the witness protection unit, in the impressive cast list for Protection.

Line of Duty fans will remember him as Police and Crime Commissioner Rohan Sindwhani, while soap viewers will know him as baddie Dr Yusef Khan in EastEnders.

Soap fans might know that he's also popped up as Jayesh Parekh in Corrie, and Bobby Khan in Emmerdale, too!

Ace is also famous for playing Haresh Chandra in the Doctor Who spin-off The Sarah Jane Adventures between 2008 and 2011.

He's been on our screens ever since 1984, and some of his early roles include Dez in Band of Gold, Dr. Rajesh Rajah in Cardiac Arrest, Zahid in Holding On, and Tom in Grafters.

Other notable roles include DC Johnny Khan in NCS Manhunt alongside The Au Pair's David Suchet, Dave Dhillon in Grease Monkeys, Ash Aslan in New Street Law, and Ash Aslan in The Shadow Line.

More recently, he starred as Nadeem in Baptiste, Nadeem in McDonald & Dodds, and Crawley in Alex Rider.

He's been in multiple film roles, too, including Bohemian Rhapsody, Bend it Like Beckham, and Last Christmas.

Andrew Knott stars as DCI Richard Bewley

Manchester-born actor Andrew Knott, 45, stars as DCI Richard Bewley, an experienced and energetic detective who has spent years in a losing battle against organised crime.

Andrew has been on our screens ever since his first appearance as a child star in the BBC drama Children's Ward.

As a young boy, he also played Dickon in the 1993 film The Secret Garden. He went on to portray Liam Shepherd in Coronation Street in 1997, and Henry Green in Where the Heart Is, a role he played between 1997 and 2001.

Other notable roles include Ben McIntyre in Drop Dead Gorgeous, Rob in Spooks: Code 9, and DS Lee Miekel in Black Work opposite Sheridan Smith.

More recently, he's starred as Dean Dobson in Ackley Bridge, Jim in Maryland, and Dirtbox in Gavin & Stacey.

Alec Newman portrays Eddie Crowther

Scottish actor Alex Newman, 50, stars as prosperous businessman Ed Crowther, who sidelines as a dangerous criminal. He's probably best known for playing Michael Byrne in Waterloo Road, a role he played from 2011 to 2013.

He's also famous for portraying Pavel Kuragin in Strike Back, and suspect Niven Guthrie in Shetland series 6.

Other notable roles include Euan Harries in Hope Springs, Robert Ludlow in Casualty, Ray Williams in Rogue, Leon Tell in The Bastard Executioner, and Ziggy Malkiewicz Snr in Karen Pirie series 1.

Alec is also known for his extensive theatre work, and his multiple roles in films including The Boys in the Boat, Code of Silence, and The Snowman.

Who else appears in the cast of Protection?

Akiya Henry is DS Sue Beardsley. The character is a conscientious police officer and Liz's colleague in the witness protection unit.

Actress Akiya is best known for voicing dozens of animated TV characters in shows such as Tinga Tinga Tales, Bottersnikes & Gumbles, Bing, Moominvalley, Hilda, and Dodo.

Young actress Tilly Kaye portrays Amy McLennan, Jimmy McLennan's 12-year-old daughter. She previously played Biff in Biff & Chip, Amy Sowden in Gentleman Jack, and Calamity in Last Tango in Halifax. Not bad for an actress who is only just 13!

Kris Hitchen portrays Jimmy McLennan, a white-collar career criminal who worked as Eddie Crowther's accountant. The actor is famous for playing dodgy copper John Hudson in Trigger Point, and DC John Nunn in The Long Shadow.

Jodie Price stars as Liz's daughter Jasmine. The actress recently played Sonya in One Day. Before that, she starred as Lily in Free Rein.

Tom Christian stars as DI Tommy Jardine, Wheatley's second in command in the Major Investigation Team. The actor was previously known for playing Sgt. Charlie Copperstone in Mr Selfridge, Brandon Boone in The Royals, and Marcus McBride in White House Farm.

Lucy Black plays Clara Penhurst, Liz’s younger sister. She's known for portraying DCI Sandy Mosby in Better, Mary Sowden in Gentleman Jack, Florence Petridis in The Durrells, and Hatty Laggan in Jericho.

Jonathan Cake stars as John Gibson. He's best known for playing The Shade/Richard Swift in Stargirl, Furkat in The Affair, Adam in Camping, and Buddy in Doll & Em. Desperate Housewives fans will know him best as Chuck Vance.

Protection on ITV full cast list:

Siobhan Finneran plays DI Liz Nyles.

Katherine Kelly portrays DCI Hannah Wheatley.

Nadine Marshall is DCI Amanda Kelman.

Barry Ward stars as DC Paul Brandice.

Chaneil Kular stars as DS Raj Kholi.

David Hayman plays Sid Nyles.

Nichola Burley portrays Gemma Brandice.

Akiya Henry is DS Sue Beardsley.

Tilly Kaye portrays Amy McLennan.

Catherine Tyldesley stars as Helen McLennan.

Kris Hitchen portrays Jimmy McLennan.

Jodie Price stars as Jasmine Nyles.

Ace Bhatti portrays DCI Arun Kapoor.

Tom Christian stars as DI Tommy Jardine.

Lucy Black plays Clara.

Alec Newman portrays Ed Crowther.

Jonathan Cake stars as John Gibson.

Nick Moss - aka Old Dog in Slow Horses - plays Freddie Howard, Jasmine's dad.

Carnival Row's Waj Ali stars as Soran Ahmadi.

The Catch's Ian Pirie plays ACC Rory Davenport.

Hijack's Zora Bishop portrays Rezan Crowther.

Reuven Walker - aka Young Vinnie in Brassic - is Arlo Crowther.

Protection starts on Sunday, March 16, 2025 at 9pm on ITV1. The whole series streams from 7am that day on ITVX.