Draw the curtains, turn off the light. It's the last Inside No 9, sob, and it's a genuine fright fest. In The Harrowing Helen McCrory and Reece Shearsmith play two creepy reclusive siblings, Tabitha and Hector,  who offer schoolgirl Katy (Aimeé-Ffion Edwards) £88 to house-sit for them for eight hours while they have a rare night out. All Katy needs to do is keep an eye on things and, under no circumstances, visit their sickly brother Andras in the top room…