John Barrrowman makes me weary. He’s always switched on. Where us mere mortals have our days where we just want to ignore the world and drink gallons of tea, followed by biscuit after biscuit, you get the impression that, somewhere in the world, John Barrowman is belting out musical numbers and laughing like a drain. Naturally, it’s not his fault, more mine. It’s this ridiculous enthusiasm for the world that has seen him become a firm fave of the people of the UK.

So with that, I bet a lot of you would like to know what made him who he was. In that case, you should tune into John Barrowman: The Making of Me (BBC One, Thursday, 24 July, 9pm) which might not be the show you think it is.

On first glance, this looks like one of those dreadful shows that simply looks back at someone’s life and sees them sprawling on an expensive leather sofa talking about their childhood and visiting the places they first tread a board. There is an element of that to this show… but the main schtick is science. Yup. You read right.

Tackling pretty heavy subjects, this show looks at ‘nature versus nurture’. Are you born with talent? Does your upbringing determine your sexuality? All these things are tested on the Torchwood actor who reckons he was born gay and nothing in his life has externally influenced that.

So, with that in mind, Barrowman undergoes a series of tests including map-reading, a brain scan, a DNA evaluation and an assessment of his reaction to pornography. I’m guessing that a ‘female brain’ would react differently to a ‘male brain’ in all of these cases… although I would take umbridge with the notion that a gay man has a ‘female brain’. Surely they have a gay man brain? Either way, this’ll be a fun romp through some normally heavy topics.