Co Armagh actor Richard Dormer played the popular character in season one of the award-winning series and fans were left devastated when he was killed in episode five.
With Gerry well liked for his ability to ease tension with witty one-liners, co-writers Declan Lawn and Adam Patterson say they are often questioned by fans about why they decided to kill him off.
It’s not clear in what capacity the Game of Thrones actor will appear in the next series.
Gerry Cliff won hearts as the easy-going veteran and mentor for rookie officers at the fictional Blackthorn Station, especially for Tommy Foster (Nathan Braniff) and Jen Robinson (Hannah McClean).
When working on a Dublin registration plate tip, Gerry and Jen unknowingly stumbled into a drug-for-arms deal involving the infamous McIntyre crime family. The popular cop then met his untimely demise at the hands of syndicate member Sully, who shot him. Retaliating, rookie officer Jen shot the gangster dead, though her mentor died in her arms. This led the young officer to leave the force and become a solicitor.
Season four will see constables Grace Ellis, Tommy Foster and Annie Conlon three years into their jobs as response officers, operating at their limit and facing a new threat on the streets that the police can barely control.
Meanwhile, 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, the constables must find the courage to face the greatest threat they have ever encountered: the truth.
Both McClean and Jonathan Harden will star, the latter playing disgraced former inspector David ‘Jonty’ Johnston in an episode that will answer important questions from the past.
Richard Dormer as Gerry Cliff in Blue Lights
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The upcoming fourth season of the Bafta and RTS award-winning series is speculated to be released this September.
Co-creators Declan Lawn and Adam Patterson said: “We’re very excited to bring this series of Blue Lights to audiences. It reveals a lot of dark secrets, examines what justice looks like in Belfast today, and ties together the past, present and futures of Grace, Annie and Tommy in an action-packed story. We can’t wait to start filming it.”
Stephen Wright, from Two Cities Television, and Louise Gallagher, of Gallagher Films, said: “We are delighted to get the cast and crew back together for series four and welcome some new faces to the Blue Lights team. The appreciation for the show means so much to everyone involved and illustrates the power of fantastic teamwork.”
BBC drama commissioning editor Nick Lambon said: “Blue Lights has gripped and entertained millions of viewers across three series, and Declan and Adam’s scripts will once again have us all on the edge of our seats. Gerry Cliff was such an integral part of series one, so to have Richard Dormer back alongside our talented cast is a dream come true.
“We are over the moon to be back filming in Belfast, and with so many twists and turns in store, fans of Blue Lights have plenty to look forward to.”