Taking the witness stand in court, Lisa prepares to recount the ordeal she suffered at Derek's hands, but she's soon stunned when Zak turns up unexpectedly - ignoring her plea to stay away from the case.
Feeling the pressure with Zak watching on, Lisa struggles to remain focused as she is cross-examined by Derek's defence barrister.
After struggling on the stand, Lisa fears that she's scuppered her chances of getting justice. Will Derek get away with his crimes?
Emmerdale airs tonight at 7pm on ITV1.
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