Jason Merrells has said his Emmerdale character is now "capable of anything".
The actor admits that he believes his character in the spa is extremely volatile, following last night's violent scenes.
Viewers were shocked to see Charity bludgeoned over the head with a meat tenderiser after she attempted to attack Declan with an axe.
Credit: ITVSpeaking to The Sun, Jason said: "He's ruthless and can be psychopathic. So once his whole world has been turned upside down by the one thing he loved, then he's capable of anything."
A showdown between the pair has been imminent after Declan learned his wife aborted their baby, and he's even been poisoning her drink to try and get rid of her.
A surprising turn of events tonight will see Charity wake and try to fight off Declan, but somebody won't come out of the situation alive.
The actor hinted the storyline will thrill viewers as it progresses: "It's a massive storyline. I think there will be moments when viewers are scared and they jump.
"What I found scary is the matter-of-factness. He's almost saying to Charity, 'Just be practical, this has got to happen'."
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