Katherine Kelly sets the scene for new ITV domestic horror in which she plays a single mother with a son who has very unusual powers

TV Times is observing a tense exchange inside a cramped living room on a leafy street in suburban London.

We’re on the set of ITV’s new three-part domestic horror, which follows a fractured family struggling with life after a divorce, and at the centre of it all is a nameless 17-year-old boy known only as HIM (played by rising star Fionn Whitehead).

We chat to Katherine Kelly, who plays the mother of HIM…

Katherine, how does your character Hannah react when HIM starts behaving strangely?
“Hannah knows she raised HIM as a good, decent boy so she’s not sure why he’s acting this way. She puts it down to pure adolescence and doesn’t suspect for one minute that he has any powers. Well, you wouldn’t, would you? If you hear a smash and walk into the room, you’d think he’s thrown a plate against the wall, not that he’s lifted it up with his eyes! A lot of accidents happen when he’s around, but everything can be completely justified and rationalised.”

So is it also a story about life after divorce?
“Yes, everything fell apart for Hannah after husband Edward had an affair. HIM stayed with Hannah after the divorce and they had a lot of years together before her new man Victor came on the scene. They were super-close, but now Hannah has a six-month-old baby, plus Victor’s daughter Faith has just come to live with them.”

How were your own teenage years?
“I remember my brothers were horrible at around 17. And between 13 and 15 were my rubbish years. But HIM is a boy who’s become lost between two families. It’s not through neglect or lack of love; he’s just stuck in the middle. That’s what I like about the script – there aren’t any baddies, just people trying to do their best.”

Was it strange that his real name is never mentioned?
“I think you won’t even notice that nobody ever says his name, either. We always do it in TV to remind the audience who’s who, but it’s one of my pet hates because it’s not like real life. In fact, I often scribble out names in scripts. However, I have given HIM a name in my head, but I’m not telling you what it is!”

HIM Premieres on ITV on Wednesday, October 19