The BAFTA award-winning Northern Irish police drama returns with six new episodes, bringing fresh threats, unresolved secrets and mounting pressure to Blackthorn Station.
BritBox has unveiled the official trailer for the fourth season of Blue Lights, confirming that the acclaimed police drama will premiere on November 12, 2026, with new episodes released weekly through December 17.
The six-episode season returns viewers to Blackthorn Station in Belfast, where three police officers face increasingly dangerous assignments while confronting a criminal investigation that threatens to expose long-buried secrets.
The latest instalment continues the series’ exploration of frontline policing, institutional pressures and the personal consequences of working in a challenging law enforcement environment.
Blue Lights Season 4 Introduces New Threats and Unresolved Secrets
The fourth season follows Constables Grace Ellis, Tommy Foster and Annie Conlon, now three years into their careers as response officers.
With their professional and personal resilience being tested, the officers encounter a growing threat on Belfast’s streets that police are struggling to contain.
Meanwhile, the murder trial of Gerry Cliff uncovers a dangerous secret with potentially far-reaching consequences for both the police service and the criminal underworld.
As tensions escalate, Grace, Tommy and Annie must make difficult decisions about their futures while confronting revelations that could fundamentally change their understanding of previous events.
The storyline is expected to build on the interconnected investigations and character relationships established throughout the first three seasons.
Returning Cast Includes Siân Brooke, Martin McCann and Katherine Devlin
The new season brings back several established cast members, maintaining continuity with the show’s earlier storylines.
Siân Brooke (Sherlock, Trying) reprises her role as Grace Ellis, alongside Martin McCann (Trespasses, Hostage) as Stevie and Katherine Devlin (The Day of the Jackal, Vikings) as Annie Conlon.
Nathan Braniff returns as Tommy Foster, while Joanne Crawford portrays Helen McNally.
Other returning performers include Andi Osho as Sandra, Frank Blake as Shane, Abigail McGibbon as Tina, Dearbháile McKinney as Aisling and Andrea Irvine as Nicola.
Richard Dormer Returns as Gerry Cliff
One of the season’s notable developments is the return of Richard Dormer, known for Game of Thrones, Fortitude and The Day of the Jackal.
Dormer reprises his first-season role as Gerry Cliff, whose murder trial becomes central to the new storyline.
Hannah McClean also returns as solicitor Jen Robinson, alongside Jonathan Harden as disgraced former Inspector Jonty.
Their appearances are expected to help resolve important questions surrounding events from earlier seasons.
Cathy Tyson returns as private members’ club owner Dana Morgan, while Michael Smiley reprises his role as intelligence officer Paul ‘Colly’ Collins.
Production Team Returns for Fourth Season of Acclaimed BBC Drama
Blue Lights is written and executive produced by Declan Lawn and Adam Patterson.
The series is co-created and produced by Stephen Wright of Two Cities Television and co-created and co-produced by Louise Gallagher of Gallagher Films, with support from Northern Ireland Screen.
Brendan Mullin serves as producer for the fourth season.
New Season Features Two Directors
Angela Griffin, whose credits include Blue Lights Season 3 and Waterloo Road, directs the first three episodes.
Sam O’Mahoney, known for The Wise Guy, directs episodes four through six.
The series was commissioned by Lindsay Salt, Director of BBC Drama.
Executive producers include Stephen Wright, Louise Gallagher, Declan Lawn and Adam Patterson, with Nick Lambon serving as executive producer for the BBC.
Blue Lights Continues International Expansion Through BritBox
The return of Blue Lights reflects the continued international demand for British crime dramas.
BBC Studios handles global distribution for the fourth season and the previous instalments. According to the distributor, the series has been sold in more than 160 territories.
Two Cities Television, which produces the programme, operates within the STV Studios family of production labels.
For BritBox, the new season adds another established British drama to its programming lineup across markets including Canada, the United States, Australia and the Nordic countries.
The streaming service, launched in 2017 and owned by BBC Studios, specializes in British television, including crime dramas, mysteries, comedies and documentaries.
Where to Watch Blue Lights Season 4 in Canada
Canadian viewers can watch Blue Lights Season 4 on BritBox beginning November 12, with episodes arriving weekly until the December 17 finale.
The first three seasons are currently available on the streaming platform, allowing viewers to revisit earlier investigations before the new episodes arrive.
With returning characters, unresolved criminal cases and an expanding international audience, the fourth season is positioned to continue the Belfast-set drama’s established blend of police procedural storytelling and character-driven suspense.
Discover more from Wire Service Canada
Subscribe to get the latest posts sent to your email.