EastEnders viewers are convinced that Mick might be beginning to show his dark side after Zack has been getting cosy with his eldest daughter Nancy.
After Zack was teaching Frankie to drive while he was intoxicated, resulting in Nancy getting hit by a car, Mick was left reeling with him.
Mick has since learned that Zack had been acting as a personal trainer for Nancy - but the pair were getting closer than simply muscle training.
Mick threatened Zack in tonight's episode as he said: "So what were you thinking, putting my Frankie behind the wheel while you had a drink.
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