Deeply concerned for her friend, Lisa is desperate to warn Lizzie off Derek - but she knows that she won't get anywhere unless she reveals the full story.
As she's not yet ready to discuss her rape ordeal, Lisa is forced to confront Derek directly - angrily ordering him to stay away from Lizzie.
However, Derek leaves Lisa sickened by retorting that she can't tell him what to do just because they 'had a fling'. With her attempts to protect Lizzie failing, what will Lisa do next?
Emmerdale airs tonight at 7pm on ITV1.
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