What else has Jemma Redgrave been in? She played Kate Stewart in Doctor Who, and has also starred as Bernie Wolfe in Holby City and Amelia Davenport in Grantchester. She's also played Evie Wilcox in the 1992 movie Howards End, and Lady De Coury in Love & Friendship. Also, Vanessa Redgrave is her aunt and Michael Redgrave is her grandad.

Hakeem Kae-Kazim plays Adam Brookham

Who is Adam Brookham? The CEO and founder of Protech Visions, a (slightly shady) medical company.

What else has Hakeem Kae-Kazim been in? He played Georges Rutaganda in Hotel Rwanda, and Mr Scott in Black Sails. The actor's many other credits include Dynasty, Deep State, Troy: Fall of a City, Vixen, Dragons: Race to the Edge, Dominion, Pirate of the Caribbean, and 24.

Paddy Glynn plays Penny Mullery

Who is Penny Mullery? Clarissa's mother. She is suffering from dementia, and Clarissa must make some difficult decisions about her future.

What else has Paddy Glynn been in? Aside from her previous appearance as Penny in the standout 2018 episode One Day, Paddy Glynn has appeared in The Dumping Ground, London's Burning, and Mari.

Louise Jameson plays Sue Marshall

Who is Sue Marshall? The wife of a man who went missing 20 years ago.

What else has Louise Jameson been in? She's best-known for playing the Fourth Doctor's companion Leela in Doctor Who from 1977 to 1978, starring opposite Tom Baker. Since then, there's been a stint as Rosa in EastEnders, Susan Young in Bergerac, and roles in Tenko, Doc Martin, Modern Love, and the stage production of Agatha Christie's The Mousetrap.

Gillian Saker plays Carla Beaty

Who is Carla Beaty? A young woman with a personal connection to the case.

What else has Gillian Saker been in? She's starred as Bella Drake in Ripper Street and Nadine in Misfits.

Anastasia Hille plays Ann Carson

Who is Ann Carson? The sister of the missing man, whose skeletal remains have turned up in the concrete pillar of a car park.

What else has Anastasia Hille been in? Recent roles have included Gael Reardon in Keeping Faith, Celia Baptiste in The Missing and its follow-up Baptiste, Rita Bellows in Wanderlust, and Dr Inge Horvath in Mamma Mia! Here We Go Again (you can spot her in the When I Kissed the Teacher number). Other credits have included Snow White and the Huntsman, The Abandoned, Not Safe for Work, and Humans.

Nicola Stephenson plays Grace Beaty

Who is Grace Beaty? Like her daughter Carla, she has a connection to the case.

What else has Nicola Stephenson been in? She's recently starred as Julie Hubble in children's TV show The Worst Witch. Previous roles have included Tess in Emmerdale, Allie Westbrook in Waterloo Road Louise Mancetta in Homefront, Sarah Williams in The Chase, Julie Fitzjohn in Holby City, and Suzie Davidson in Clocking Off.

Clive Wood plays Paul Simmons

Who is Paul Simmons? Boss of the company which built the car park.

What else has Clive Wood been in? Aside from his stage career, Clive Wood has played Bill Crowthers in Casualty, Croome in Sense8, Matt Kerr in Press Gang, and DCI Wray in The Bill. On the big screen he's been in Suffragette, Salmon Fishing in the Yemen, and All the Money in the World.

Cory Chambers plays DC Matthew Quinn

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Who is DC Matthew Quinn? DI Raymond's sidekick.

What else has Cory Chambers been in? He played Bello in Slaughterhouse Rulez.

Episode 5 & 6 guest stars

Zoë Harrison plays Jenny Shaw AND Carol Alexander

Who is Jenny Shaw? A woman who is found dead on the train tracks. It quickly emerges that she suffered domestic violence.

Who is Carol Alexander? Nikki's mum. As Nikki looks back on her own childhood and is forced to confront memories of domestic violence within her own family, the same actress is used to play both women.

What else has Zoë Harrison been in? She played Jessica in the TV series Cloud 9, and was Young Maria in Never Let Go.

Garry Robson plays DI Sid Clarke

Who is DI Sid Clarke? The Detective Inspector assigned to the case.

What else has Garry Robson been in? Screen credits include Pitching In and Casualty – and he has actually previously appeared in Silent Witness, playing a character called Chris Ward in a storyline from 2005. He's also a stage actor, writer, director and performer who has worked to highlight the work of disabled colleagues.

Stephen Walters plays Robbie Shaw

Who is Robbie Shaw? Jenny's husband.

What else has Stephen Walters been in? He's had a ton of TV roles in recent years, including Thomas Malone in Shetland, Johnny in Tin Star, DCI Mark Guinness in Little Boy Blue, and Angus Mhor in Outlander. Further back, he's also made appearances in Layer Cake, Revolver, Hannibal Rising, and Batman Begins.

Ellie Dadd plays Cat Shaw

Who is Cat Shaw? Jenny and Robbie's daughter. She has been through a lot in her short life.

What else has Ellie Dadd been in? Aside from a role in 2013 short film Lipstick, this is her first on-screen appearance.

Gabrielle Glaister plays Donna Collyer

Who is Donna Collyer? Jenny's mother, and Cat's grandmother.

What else has Gabrielle Glaister been in? Gabrielle Glaister has had a recent stint as Hilary in Emmerdale. She played Alison Pinion in series three of Unforgotten, and appeared as wedding planner Juliet Evans in Midsomer Murders episode Till Death Do Us Part. Other notable roles have included Trish Wallace in Family Affairs, Debs Brownlow in Coronation Street, and Patricia Farnham in Brookside. Back in the '80s, she also popped up in Blackadder Goes Forth and Blackadder II.

Maddy Collings plays Young Nikki

Who is Young Nikki? We meet five-year-old Nikki Alexander in flashbacks throughout episodes five and six.

What else has Maddy Collings been in? This is her first TV appearance.

Geoff Bell plays Brian Collyer

Who is Brian Collyer? Donna's husband, and Jenny's father. He works as a mechanic.

What else has Geoff Bell been in? Recently, he's been on our screens as Jack Verhoeven in His Dark Materials and as Carl Wood in Hatton Garden. Previous roles have included Fabian in Wild Target, Dean in Kingsman: The Secret Service, Tommy Hatcher in Green Street, and Duncan Elliot in The Level. That's also him as "The Boss" in Louis Tomlinson's music video for Don't Let It Break Your Heart.

Raymond Coulthard plays Det. Supt. Donald Hart

Who is Detective Superintendent Donald Hart? A police bigwig who becomes closely involved with the case. He likes to take charge and throw his weight around, and soon gets everyone's backs up. Donald Hart is also trying to draw Thomas into his own sphere – introducing him to people at his Gentleman's Club and suggesting ways to advance his career.

What else has Raymond Coulthard been in? Having started out starring as Young Ebenezer Scrooge in 1992's The Muppet Christmas Carol, Raymond Coulthard has gone on to play James Schofield in Hotel Babylon, Miles Edgerton in Mr Selfridge, Jacob Pasha in Da Vinci's Demons, Mark Radcliffe in The Infinite Worlds of HG Wells, and Rupert Douglas in Oscar-winning movie The English Patient. He's seen above in a production of Shakespeare's Measure for Measure.

Janine Wood plays Sharon Evelina

Who is Sharon Evelina? Sharon works at a Women's Refuge in London, where she provides support to abused women and runs the house.

What else has Janine Wood been in? She played Mary Hughes in Rocket Man (the 2005 TV series, not the hit Hollywood movie) and starred as Clare France in After Henry, as well as playing Frances Earnshaw in the 1992 adaptation of Wuthering Heights. Recent credits have included Call the Midwife (as a welfare officer) and Doctors (as Jenny Sinclair). This also isn't the first time we've seen her in Silent Witness; she played a lawyer called Elizabeth Dunn QC in an episode in 2014.

Sian Reese-Wiliams plays Tina Harcourt

Who is Tina Harcourt? One of the women at the women's refuge. She and her ex-husband Peter have two young girls, and they're embroiled in a fight over custody and visitation arrangements.

What else has Sian Reese-Wiliams been in? The actress made a brief but memorable appearance in series five of Line of Duty, playing PS Jane Cafferty (above). She's also been DCI Cadi John in the TV series Hidden, Trudy Franken in Requiem, and Manon in Hinterland. Sian Reese-Williams first hit the small screen as Gennie Walker in Emmerdale, a role she played for five years.

Ben Caplan plays Peter Harcourt

Who is Peter Harcourt? Tina's abusive ex-husband.

What else has Ben Caplan been in? You're most likely to recognise him as PC (later Sergeant) Peter Noakes from Call the Midwife – that is, husband of Miranda Hart's Chummy (above). His other roles have included Smokey Gordon Jr in Band of Brothers, Michael Freeland in New Blood, and Frank in The Commuter.

Michael Maloney plays Judge Lansing

Who is Judge Christopher Lansing? A judge at the Family Court. He also went to school with Thomas, and is pals with the Detective Superintendent.

What else has Michael Maloney been in? Most recently, you may have seen him as Prime Minister Edward Heath in season three of The Crown, or as Lord Bill Astor in The Trial of Christine Keeler (above). As a prolific actor with almost 150 screen credits to his name, Michael Maloney has also appeared in The Five, Paranoid, The Young Victoria (as Sir Robert Peel), Notes on a Scandal, and Coronation Street.

Isis Davis plays Cheryl Wilkes

Who is Cheryl Wilkes? An abused woman who has been staying at the women's refuge. She's just gone back to her boyfriend, Owen (Liam Ainsworth).

What else has Isis Davis been in? She's had a handful of roles in TV shows including Electric Dreams and EastEnders, and movies including Bruno and Lie Low.

Alexa Davies plays Lucie Hudson

Who is Lucie Hudson? A woman who has just left the refuge to reunite with her girlfriend, who's due to be released from prison.

What else has Alexa Davies been in? She's been playing Julie Mugford in White Hhttps://www.radiotimes.com/tv/drama/itv-drama-white-house-farm/ouse Farm, and also starred as Meg in Dead Pixels. Previous shows have included Detectorists (playing Kate), Harlots (playing Betsey Fletcher), and Raised by Wolves (playing Aretha).

Seraphina Beh plays Jade Brandyce

Who is Jade Brandyce? Lucie's abusive girlfriend, who is just out of jail.

What else has Seraphina Beh been in? She played Farah in Top Boy, and is known for starring as Madison Drake in EastEnders.

Episode 3 & 4 guest stars

Will Thorp plays Peter Forbes

Who is Peter Forbes? A bereaved father, whose son Jason disappeared on his way home from judo training. Six months later, the boy's body has been found – and Peter demands answers.

What else has Will Thorp been in? Having spent some time playing Paul 'Woody' Joyner in Casualty, Will Thorp went on to play Chris Gray in Coronation Street a few years later. He played the character Toby Zed in David Tennant-era Doctor Who, and is also a prolific stage actor and narrator of audiobooks – lending his voice to a series of Doctor Who novels.

Lily Bevan plays Tina Forbes

Who is Tina Forbes? Jason's mother. She is devastated by the loss of her son, who was a judo champion.

What else has Lily Bevan been in? The actress played Emily in Doctor Who episode The Waters of Mars.

Sophia Di Martino plays DCI Claire Ashby

Who is DCI Claire Ashby? The Senior Investigating Officer in the Jason Forbes case. Young and ambitious, Claire has quickly reached the rank of DCI.

What else has Sophia Di Martino been in? Having played Amber in Mount Crescent, Amy in Channel 4's Flowers, Carol in Yesterday, and Lily in Into the Badlands, Sophie Di Martino will soon be appearing in the hotly-anticipated Disney+ series Loki.

Charles Babalola plays DS Mike Macneil

Who is DS Mike Macneil? Claire's Detective Sergeant.

What else has Charles Babalola been in? Most recently, he was seen playing another Detective Sergeant – DS Andy Bevan – in the ITV crime thriller Bancroft. Other credits include Kulonga in The Legend of Tarzan, Andrew in Mary Magdalene, Tusk in Black Mirror episode Hated in the Nation, DS Jesse Rawlins in Thirteen, and Ade in Stan Lee’s Lucky Man. He also starred opposite Bryan Cranston in a stage production of Network.

Tom Goodman-Hill plays AC Tim Holloway

Who is AC Tim Holloway? The Assistant Commissioner. He knows Clarissa from a case they worked on together years ago, and now he's come to the Lyell Centre with the Jason Forbes case instead of the local pathology lab. DCI Claire Ashby is his protégé.

What else has Tom Goodman-Hill been in? Recently he starred opposite Molly Windsor and Katherine Kelly in ITV drama Cheat, playing Adam. Tom Goodman-Hill is also known for playing Joe Hawkins in Humans, and has appeared in Everest, The Imitation Game, and Mr Selfridge.

Andre Flynn plays Malcolm Wilde

Who is Malcolm Wilde? The obvious suspect in the Jason Forbes murder. He works as a locksmith.

What else has Andre Flynn been in? After starting out with a role as Gaston in The Musketeers in 2016, the young actor has appeared in Jamestown (above), Papillon, and Blue Iguana.

Robert Pugh plays Robert Wilde

Who is Robert Wilde? Malcolm's father.

What else has Robert Pugh been in? The Welsh actor played Craster in Game of Thrones, and in recent years has starred as Mr John Osborne in Vanity Fair, Jack Reynolds in Doctor Foster, and Lord Wynnstay in Mr Selfridge – alongside Silent Witness co-star Tom Goodman-Hill (above). This is actually Robert Pugh's third appearance in Silent Witness: he's also popped up as different characters in 1999 and 2008.

Phil Davis plays Mick Ramsden

Who is Mick Ramsden? You'll have to wait and see...

What else has Phil Davis been in? As a prolific character actor, Phil Davis has appeared in Vera Drake, Bleak House, Notes on a Scandal, Hampstead, Riviera, and Being Human. He was Jud Paynter in Poldark, and played DS Ray Miles in Whitechapel. Last time he appeared in Silent Witness he was playing "Derek Pargeter" in a couple of episodes from 2008.

Episode 1 & 2 guest stars

Emma Cunniffe plays Jess Fisher

Who is Jess Fisher? In episode one, a private jet has crashed after getting into trouble in British airspace. Jess Fisher is an expert from the AAIB (Air Accidents Investigation Branch), who will work closely with the forensics team and the police to figure out the cause of the crash.

What else has Emma Cunniffe been in? Previous roles have included Janet in series two of Unforgotten, DS Hawthorn in Coronation Street, and Dr Janet Fielding in Doctors. The actress played Claire in a 2011 episode of Doctor Who, Night Terrors.

Adjoa Andoh plays DI Nina Rosen

Who is DI Nina Rosen? The detective investigating the plane crash.

What else has Adjoa Andoh been in? If she sounds familiar, it may be because she's the voice of Colonel Casey in Thunderbirds Are Go. Adjoa Andoh's acting credits include Brenda Mazibuko in Invictus, Dr Jacobs in Fractured, Margaret Rust in Liar, and Francine Jones in Doctor Who – that is, Martha's mum. She'll soon star as Lady Danbury in the upcoming TV drama Bridgerton.

Matthew Brenher plays Jonathan Kraft

Who is Jonathan Kraft? The ex US ambassador, who was a victim of the plane crash. He was also close friends with Nikki's boyfriend Matt.

What else has Matthew Brenher been in? He starred as Eldar Grossman in Palo Alto, and is also a prolific voice actor in video games (and more).

Rebecca Oldfield plays Miriam Heller

Who is Miriam Heller? Head of a charity, the Global Crisis Committee, and a passenger on the plane. Her 11-year-old son Ezra (played by newcomer Harrison Abel) was also "along for the ride" on the plane when it crashed.

What else has Rebecca Oldfield been in? She played trainee engineer Erina Lessak in an episode of Doctor Who, and has actually previously appeared in Silent Witness already - playing a character called Miranda Anscombe back in 2006.

Okezie Morro plays Michael Heller

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Who is Michael Heller? Miriam's husband, and Ezra's father. He received a distressed phone call from his son while the jet was in trouble.

What else has Okezie Morro been in? Okezie Morro starred as Bryan Hunt in the spooky sci-fi/horror series The Mist, and appeared as Ekene in TV series Shuga.

Edward Hogg plays John Stanley

Who is John Stanley? A psychotherapist. Pilot Rowan Cole was one of his private patients.

What else has Edward Hogg been in? In the last few years, Edward Hogg has been seen as Thomas Haxby in Harlots, Godfrey in Taboo, and Varr in Beowulf: Return to the Shieldlands. He's also made appearances in Jupiter Ascending, Nicholas Nickleby, and Jonathan Strange & Mr Norrell.

Mat Fraser plays Jim Bell

Who is Jim Bell? Jim is involved in a secret chatroom for troubled men.

What else has Mat Fraser been in? He recently starred in His Dark Materials as a Gyptian, Raymond van Gerrit. Other shows include Loudermilk (as Roger), American Horror Story (as Paul the Illustrated Seal), Cast Offs (as Will), Unarmed But Dangerous (as Jimmy Loveit), and a production of Shakespeare's Richard III as the monarch himself. Mat Fraser, who has thalidomide-induced phocomelia, is also a musician and drummer who's played in a series of rock bands and performed at the 2012 Paralympics opening ceremony.

Nathaniel Martello-White plays Kyle Cunningham

Who is Kyle Cunningham? Kyle is involved in a secret chatroom for troubled men.

What else has Nathaniel Martello-White been in? Aside from his work on the stage, Nathaniel Martello-White has appeared in TV thriller Collateral (as DS Nathan Bilk), Kiri (as Ade), and Guerrilla (as Dhari Bishop).

Stephanie Levi-John plays Kate Woodman

Who is Kate Woodman? Kyle's wife or partner. Their relationship is troubled after the loss of their young son.

What else has Stephanie Levi-John been in? She played Lina de Cardonnes in The Spanish Princess, and appeared as a cop in the Not Going Out Halloween Special.

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Florisa Kamara plays Ella Cunningham

Who is Ella Cunningham? Kyle and Kate's daughter.

What else has Florisa Kamara been in? The young actress stars as Donna in the Sky drama Bulletproof.