Lachlan (played by Thomas Atkinson) is already an intensely volatile member of the White family, but his vengefulness has reached new heights.
The plot saw a smug Robert (Ryan Hawley) continue to hold a vice-like grip over the clueless Lawrence (John Bowe), after he convinced him he had passionate feelings for the elderly man.
What he wasn't prepared for was for Lawrence's grandson Lachlan to walk in on them about to indulge in a passionate embrace.
"Get away from him," the youngest White snapped venomously.
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I know I'm right about you
Despite attempting to get his grandad to see reason, Lachlan went one step too far with his rage-filled accusations and Lawrence eventually had enough.
Telling him he had to leave Home Farm for good, Lawrence left Lachlan packing his bags and seething at infiltrator Robert.
Catching him before he departed, Robert gave him some biting last words, which may serve as ammunition for Lachlan's subsequent revenge, as teased in upcoming spoiler pictures of the ITV soap.
"I know I'm right about you," Lachlan muttered coldly.
Emmerdale's most shocking moments
Thu, January 5, 2017
Emmerdale's most shocking moments: Explosions, car crashes and murder – life in the Dales is never dull. Here are the most dramatic scenes from the popular soap.
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Emmerdale: Robert is blissfully unaware of the lengths Lachlan will go to
"Nobody believes you, not even your mum," Robert replied with a chilling smile. "I don't see her, running out here, offering to come with you."
The character continued to torment Lachlan, saying: "Still, at least I'm not taking your car. You could sleep in that?
"Face it, you lost," he added before shutting the double doors on his rival.
Emmerdale continues tomorrow at 7pm on ITV.