BBC's second series of the hugely popular police drama Blue Lights is returning on Monday, April 15. The new season follows exactly one year after the first series and will see Siân Brooke, Martin McCann, Katherine Devlin, Nathan Braniff, Joanne Crawford, and Andi Osho reprise their roles.

A synopsis reads: "Belfast city centre is awash with drugs and beset by street crime. Our response officers Grace, Annie and Tommy are no longer wide-eyed rookies, and are beginning to feel the personal and psychological effects of relentless and punishing police work." The second series is set to dig deeper into the character's lives and understand why they react in certain situations, following their introduction to BBC viewers in series one.

On what audiences can expect from the second series, Sian, who place Grace Ellis, said: "The stakes are high. It will be quite explosive, moving and an authentic reflection of some parts of present-day Belfast, but audiences can still expect those comedy beats alongside the serious side of the story."

READ MORE:BBC announces return of huge drama eight years after explosive season one finale

LATEST: Wynne Evans and Joanna Page join forces to present brand new BBC series

But when does Blue Lights start, who is in the cast, who did series one end and what can viewers expect? Here's everything you need to know.

When does Blue Lights series two start?

Blue Lights series two will be available in full on BBC iPlayer from 6am on Monday, April 15, while the first episode will air on BBC One from 9pm, with subsequent episodes airing weekly.

BBC Blue Lights series one recap

Blue Lights Series 2 characters Stevie Neil (Martin McCann), Grace Ellis (Sian Brooke), Annie Conlon (Katherine Devlin) and Tommy Foster (Nathan Braniff)
Blue Lights Series 2 characters Stevie Neil (Martin McCann), Grace Ellis (Sian Brooke), Annie Conlon (Katherine Devlin) and Tommy Foster (Nathan Braniff)

Series one of Blue Lights wrapped up in May 2023 with a tear-jerking episode. The last instalment of the season ended with the heartbreaking death of Gerry, who passed away after being shot multiple times in the penultimate episode by Sully.

Elsewhere, the McIntyres were arrested by the team after their location came to light and Stevie came close to admitting his feelings to Grace before a call came in over police radio and sent him on a job. The finale also saw Jen resign from the force, although the character will appear in series two.

Creators, writers, directors and producers of Blue Lights, Declan Lawn and Adam Patterson, have spoken about how series two has been elevated from the first series. Declan said: "Series two is bigger, bolder and more dramatic. Series one was about our recruits having their feet held in the fire and in series two they are firmly in the fire.

"The city is under siege with drugs and petty crime and they can’t work out what’s going on nor do they have the resources to deal with it. At the heart of the series is a story about a veteran, Lee Thompson, who returns to see the place he has grown up in torn apart by drugs and crime. He decides to wage a one-man revolution against the loyalist godfathers and it causes total chaos for our police officers and the city in general. Everything spirals out of control and the pressure grows."

While Adam added: "In series one we had three new recruits in an alien world but they are now a year into the job and we see them taking a few more risks. Creatively, we are also taking more risks. There’s a lot of Belfast to look at and we wanted to shine a light on different parts of the city. One of the unifying themes about series two is how difficult it is to initiate change and our young loyalist rebel wants to change his home environment for the good but ends up having to do bad things in order to change that system. It’s about how far can you go to try and do good in the world. It’s all about the grey which is where Blue Lights lives."

BBC Blue Lights full cast list

Martin McCann and Sian Brooke in the drama

Siân Brooke - Grace Ellis

Martin McCann - Stevie Neil

Katherine Devlin - Annie Conlon

Nathan Braniff - Tommy Foster

Joanne Crawford - Inspector Helen McNally

Hannah McClean - Jen Robinson

Andi Osho - Sergeant Sandra Cliff

Desmond Eastwood - Detective Murray Canning

Andrea Irvine - Chief Superintendent Nicola Robinson

Frank Blake - Shane Bradley

Jonathan Harden - Inspector David ‘Jonty’ Johnson

Derek Thompson - Robin Graham

Seamus O’Hara - Lee Thompson

Seána Kerslake - Mags Thompson

Alfie Lawless - Henry Thompson

Abigail McGibbon - Tina McIntyre

Paddy Jenkins - Happy Kelly

Dan Gordon - Rab McKendry

Dearbhláile McKinney - Aisling Byrne

Where was BBC Blue Lights filmed?

Blue Lights Series two's Lee Thompson and Mags

The drama was set and filmed in Belfast. Writers Adam and Declan have said that Belfast is "more of a character" in this series and viewers can "see the full spectrum of the city which is good". Adam added: "Stylistically in series two we wanted to evolve and show more of Belfast and I don’t just mean having more shots of officers in Belfast but standalone shots of the city that mean something to the storyline.

"We really worked hard to find the tapestry and the blanket imagery that would lead into our worlds and people and that led to it feeling more visceral and real. We wanted to show more of this place that we love but that is still in many ways troubled."

How many episodes of BBC Blue Lights are there?

There are six episodes of Blue Lights in series two. All six episodes are available to binge on BBC iPlayer now, otherwise the new series kickstarts on BBC One on Monday, April 15 at 9pm with episodes airing on the channel weekly. You can keep up to date with the latest TV and showbiz news by signing up to the newsletter here.