The Bill: The Apple and the Tree

As the relief frantically searches for Cathy, she leaves a series of clues in a bid to lure them closer to her hiding place in the boiler room - but when they still fail to pinpoint her, she turns off the heating and clobbers the engineer sent to fix the problem, then leaves the unfortunate bloke's unconscious body outside the door as bait. When the team finally put two and two together, Cathy will only speak to Brandon - and more worryingly, she refuses to give any indication as to whether or not his kids are still alive