Back in 2024, it was confirmed that hugely popular crime drama Blue Lights would be returning for not only a third season, but a fourth run as well.
While season 3 aired last year, season 4 is now finally here, reuniting fans with the PSNI team including Grace (Siân Brooke), Tommy (Nathan Braniff) and Annie (Katherine Devlin).
This season will see the return of some long absent characters, including Richard Dormer's Gerry, who was killed in season 1 but is returning this time around for a flashback episode.
The synopsis for season 4 says: "The murder trial of Gerry Cliff exposes a dangerous and long-buried secret that leads to chaos both inside the police and across the criminal underworld. As they grapple with big decisions about their future, Grace, Tommy and Annie must find the courage to face the greatest threat they have ever encountered: the truth."
But who else is back in the cast for the new batch of six episodes?
Read on for everything you need to know about the cast of Blue Lights season 4.
The confirmed cast for Blue Lights season 4 are as follows. Scroll on to find out more about their characters, plus scroll further for information on previous season's characters.
- Siân Brooke as Grace Ellis
- Martin McCann as Stevie Neil
- Katherine Devlin as Annie Conlon
- Nathan Braniff as Tommy Foster
- Joanne Crawford as Helen McNally
- Andi Osho as Sandra Cliff
- Frank Blake as Shane Bradley
- Abigail McGibbon as Tina McIntyre
- Dearbháile McKinney as Aisling Byrne
- Neil Keery as Lawrence McCloskey
- Andrea Irvine as Nicola Robinson
- Michael Smiley as Paul 'Colly' Collins
- Richard Dormer as Gerry Cliff
- Cathy Tyson as Dana Morgan
- Hannah McClean as Jen Robinson
- Jonathan Harden as 'Jonty' Johnston
Siân Brooke plays Grace Ellis
Who is Grace Ellis? Grace is an empathetic and caring former social worker who is now a constable in the Police Service of Northern Ireland. No longer a new recruit, Grace is navigating career challenges and her relationship with Stevie.
Where have I seen Siân Brooke? Brooke is best known for her roles as Eurus Holmes in Sherlock, Deirdre Young in Good Omens, Aemma Arryn in House of the Dragon and Karen in Trying. She has also had roles in The Terror, Doctor Foster, Supacell, The Undeclared War and more.
Martin McCann plays Stevie Neil
Who is Stevie Neil? Stevie is a sergeant and Grace's former mentor, who was tasked with getting her through her probation. They are now in a relationship and live together.
Where have I seen Martin McCann? McCann has previously appeared in series such as Marcella, The Fall, Vera, Temple, Say Nothing, Hostage and Trespasses, as well as films including Clash of the Titans and '71.
Katherine Devlin plays Annie Conlon
Who is Annie Conlon? Annie is one of the constables in the PSNI, who joined around the same time as Grace.
Where have I seen Katherine Devlin? Blue Lights is Devlin's first major role, after she previously appeared in 2018 film The Dig and one episode of Vikings. She has since appeared in an episode of The Day of the Jackal.
Nathan Braniff plays Tommy Foster
Who is Tommy Foster? Tommy is another constable in the PSNI who joined at the same time as Grace and Annie. He is in a relationship with Aisling, but it was heavily tested in season 2.
Where have I seen Nathan Braniff? Blue Lights is Braniff's first on-screen role.
Joanne Crawford plays Helen McNally
Who is Helen McNally? Helen is the Inspector in the PSNI team, having been promoted following the departure of Jonty.
Where have I seen Joanne Crawford? Crawford is known for her roles in series such as Line of Duty, The Fall, Chosen, Dead and Buried and Outlander: Blood of My Blood, as well as films including Ballywalter, To All My Darlings and Small Things Like These.
Andi Osho plays Sandra Cliff
Who is Sandra Cliff? Following the death of her husband Gerry in season 1, Sandra is no longer the main custody sergeant at the police station, but has instead been promoted to be the section’s skipper.
Where have I seen Andi Osho? Osho is known for her roles in series such as Good Omens, Sex Education, You & Me, The Sandman, Breeders, Stay Close, Line of Duty, I May Destroy You and Death in Paradise, as well as the DC film Shazam!.
Frank Blake plays Shane Bradley
Who is Shane Bradley? A constable who arrived in season 2. He was stabbed in the leg in season 3 but is now back on duty. He and Annie have previously had a romantic connection.
What have I seen Frank Blake before? Blake played Alan in the TV adaptation of Sally Rooney's Normal People. He has also appeared as Declan Fraser in Sanditon, and in series such as Say Nothing and Trespasses.
Abigail McGibbon plays Tina McIntyre
Who is Tina McIntyre? Tina is the matriarch of the McIntyre crime family, operating in Belfast.
What have I seen Abigail McGibbon before? McGibbon has had roles in series including The Power of Parker and The Lovers.
Dearbháile McKinney plays Aisling Byrne
Who is Aisling Byrne? Aisling is a member of the PSNI team who is in a relationship with Tommy, but they faced difficulties as a couple in season 3 as she struggled with PTSD, and started to behave erratically.
Where have I seen Dearbháile McKinney? McKinney has featured in Kneecap, Murder Most Puzzling, Malpractice and Derry Girls.
Neil Keery plays Lawrence McCloskey
Who is Lawrence McCloskey? McCloskey is a firearms officer with the PSNI.
What have I seen Neil Keery before? Keery has had roles in series including Game of Thrones, Emmerdale, Vikings, Say Nothing and How to Get to Heaven From Belfast.
Andrea Irvine plays Nicola Robinson
Who is Nicola Robinson? The assistant chief constable at the station.
Where have I seen Andrea Irvine? Irvine has had roles in series and films including Ella Enchanted, The Fall, Line of Duty, Red Rock, Dead Shot and Call the Midwife.
Michael Smiley as Paul 'Colly' Collins
Who is Paul 'Colly' Collins? Colly is a former mentor and acquaintance of Helen's, who now works in the world of intelligence.
Where have I seen Michael Smiley? Smiley is known for his roles in Black Mirror, Bad Sisters, Dead Still and Luther. He has also had roles in Bleak House, Wire in the Blood, Obituary and Alien: Earth, and will be seen in this year's Bookish Christmas special.
Richard Dormer plays Gerry Cliff
Who is Gerry Cliff? Gerry was Sandra's husband and a key, beloved member of the PSNI team. He was killed in season 1 by Sully, but is set to return in season 4 for a flashback episode.
Where have I seen Richard Dormer? Dormer has had roles in series including Fortitude, Game of Thrones, COBRA, Secret Invasion, The Day of the Jackal, Castlevania: Nocturne, Gangs of London and The Assassin, as well as films such as '71.
Cathy Tyson as Dana Morgan
Who is Dana Morgan? Dana runs a private members club in Belfast but there's a lot more than meets the eye to her story, as we came to find out in season 3. She actually has deep connections with the criminal underworld.
Where have I seen Cathy Tyson? Tyson is known for her roles in Criminal Record, Boiling Point, The Sandman, Dune: Prophecy, Help, Black Ops and Ride or Die. She has had various roles over the years and has also starred in Night & Day, Band of Gold and Mona Lisa.
Hannah McClean plays Jen Robinson
Who is Jen Robinson? Jen was a police constable, but she left the PSNI at the end of season 1 after the death of Gerry Cliff. When we last saw her, she was a trainee solicitor.
Where have I seen Hannah McClean? McClean has previously had minor roles in series such as Josh and Sick Note, while she has more recently appeared in Malpractice, Grace and The Running Man.
Jonathan Harden plays David 'Jonty' Johnston
Who is David 'Jonty' Johnston? Jonty was previously the Inspector in charge at the station, but he was forced to resign after it was revealed he had been having an affair with Jen, his junior. In season 2, he briefly returned to the station in a more junior position, in order to utilise his experience and knowledge.
Where have I seen Jonathan Harden? Harden is known for his roles in series including Sherwood, Time, Unforgotten, Peep Show, Ellis, Mix Tape, The Rainmaker and Grace, well as films such as Victoria & Abdul and Star Wars: The Last Jedi.
Seamus O’Hara plays Lee Thompson
Who is Lee Thompson? A Protestant from east Belfast who got caught up in a loyalist feud in season 2. At the end of season 3, he was seen teaming up with Tina McIntyre.
Where have I seen Seamus O’Hara before? Viewers will recognise the actor from his previous roles in An Irish Goodbye, Dungeons & Dragons: Honour Among Thieves, Say Nothing, Sherlock & Daughter and House of Guinness.
Desmond Eastwood plays Murray Canning
Who is Murray Canning? A detective sergeant now leading a Paramilitary Crime Taskforce, who in season 2 is investigating loyalist paramilitaries.
Where have I seen Desmond Eastwood? Eastwood has previously appeared in shows such as Blood, Normal People, Vikings and Derry Girls, along with films including In the Land of Saints and Sinners and The Last Rifleman.
Paddy Jenkins plays Happy Kelly
Who is Happy Kelly? Happy is the childhood friend of Gerry who suffered trauma and often wanted to be arrested so he wouldn't be alone. In season 2, Jen looks into a case from his past to try and help him move on.
What have I seen Paddy Jenkins before? Jenkins has had roles in Bel's Boys, Give My Head Peace, An Irish Goodbye and The Last Rifleman.
Seána Kerslake plays Mags Thompson
Who is Mags Thompson? Lee’s sister. The co-owner of The Loyal pub in Mount Eden in Belfast with her brother Lee.
Where have I seen Seána Kerslake before? Kerslake has previously starred in thriller series Smother, as well as comedies Bad Sisters and Ballywalter.
Craig McGinlay plays Craig McQuarrie
Who is Craig? Lee’s right-hand man.
Where else have I seen Craig McGinlay? McGinlay's acting credits include the TV series Cobra, You, Outlander and Knightfall.
Dan Gordon plays Rab Thompson
Who is Rab? Mags and Lee’s uncle.
Where else have I seen Dan Gordon? Gordon is best known for his roles as Noel Timoney in Bloodland, and Garda Summers in Northern Irish drama film Doineann.
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