The police officer, played by Alex Walkinshaw, 33, is forced to come clean after gun runner Kieran, played by Rupert Hill, learns his true identity.
Smithy's undercover investigation into gun smuggling draws to a dramatic close on the streets of Sun Hill as these dramatic pictures show.
Sergeant Smithy reveals his true colors to Keiran Wallace, sparking the gun fight
Sergeant Smithy ends the stand off as he fires the first shot
As the full story unravels, the pair are involved in a tense stand-off, eventually forcing Sergeant Smithy to fire the first shot.
A source tells the Star: "Kieran pushes Smithy to the edge and he's forced to reveal his true colours.
"With a machine gun pointed at his head, he's forced to pull a gun on Keiran and it's just a case of who pulls the trigger first."
Bu fans will have and wait to see who comes out alive.
Kieran lies injured on the ground but fans will have to wait if it all ends well for Sergeant Smithy
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