I can separate all the men I know into two categories: alphas and betas. Leaders and followers, if you will.

Inside Men's warehouse manager John Coniston (played brilliantly by Steven Mackintosh) is a beta, but in order to orchestrate a heist he has to become an alpha.

That's basically where this story began for me. How do I fundamentally change a man's personality? How do I use his weakness as his strength?

How do I get him to do something that just plain isn't in him?

There was some skepticism when I first pitched the idea. Heists had gone out of fashion, both in reality and in drama.

Growing up and watching TV in the late 1970s, every other week some hairy geezer was pulling a pair of nylon tights over his face and walking into a bank with a sawn-off shotgun.

If you wanted to become a millionaire overnight, armed robbery was pretty much your only option. By the time the early 1990s rolled around, credit cards and the national lottery had given criminals an easier option.

It took a couple of meetings to convince everyone that this wasn't going to be about the money. Inside Men isn't just a story about a robbery, it's about what it means to be a modern man.

Whilst researching this drama I found out that there's something like £45 billion worth of cash in the UK. Sitting in vaults, down the backs of sofas, and chinking around in our pockets.

We may think of ourselves as a cashless society, but it's still out there. And it's not worth any less.

I often use dual timelines when structuring a story. I did something similar on Worried About The Boy, flicking between 1981 and 1986. Maybe I just like to keep the audience on their toes.

With Inside Men, opening with the heist allowed me to get straight into two stories that impacted on one another. How did they plan it? And will they get away with it?

The scenes in the vault were filmed in a decommissioned Bank of England building in Bristol.

The vault door weighed four tonnes and you just can't recreate stuff like that.

I went on set one day and held one of the shotguns, pulled on a mask, and stared at the cages of bank notes. Suddenly it didn't seem so easy. 

Tony Basgallop is the writer of Inside Men.

Comments made by writers on the BBC TV blog are their own opinions and not necessarily those of the BBC.