There’s a danger that writing for screen encourages writers to think in shorthand, to use stereotypes that are familiar because they’ve been successfully used in film and television before. Don’t expect to find any insight into crime and character in Guy Ritchie’s films, in other words: they exist in relation to other fictional depictions of gangsters on screen, and not the real world as anyone I know recognises it.

Compare Lock, Stock and Two Smoking Barrels with the real life villainy depicted in Donal MacIntyre’s feature documentary A Very British Gangster, and you’ll understand why some people opt for the likes of Hugh Fearnley-Whittingstall over the joys of the burger van that pulls up outside TK Maxx on a Saturday night to catch the drinkers.

MacIntyre’s film follows the complex life of crime boss Dominic Noonan over three years, giving an intimate portrait of a family that lays down the law in its patch of Manchester. Noonan is a very bright guy, as you’d need to be to track the machinations and deal with the potential problems of a criminal empire involved in importing drugs, dispensing homegrown justice in brutal fashion, and dealing with rivalries within and outside the Noonan clan.

So far, so familiar. We’d expect a crime boss to be smart and capable. But this one is many other things too. He speaks the language of the Asian family who ensured that he was fed when he was growing up and his parents were often too busy in the cells to get dinner ready for the kids. He’s involved in helping the local community to sort its family and other problems out, sometimes acting alongside social workers to ensure that domestic situations are dealt with in ways that assist the most vulnerable. And he’s gay, which is still a surprise for some people when they think about tough guys.

Those facets aren’t contradictory, by the way: they’re human, and scratch pretty much anyone and you’ll find an equally complex mesh of drives and traits and personality quirks. If only more drama reflected that richness. Sure, there always have been some writers, directors, and actors comfortable with rounded characters, but it’d be lovely to see more.

Writers agent and founder of ScriptWriter magazine Julian Friedmann urges aspiring writers to study psychology at degree level, before doing an MA in screenwriting when they’ve got some life experience under their belts. Personally, I’m not at all convinced about the need for any qualifications, though some kind of training can help people shape raw concepts into structured stories.

I won the Times competition that secured me a meeting with Working Title’s Tim Bevan on the basis of the first film treatment I ever wrote without having seen an actual film treatment, or having much clue about what to put into one. And there are times when what I’ve applied myself to learning about the craft of screenwriting since then has got in the way of the stories I actually wanted to tell, and got me involved in projects that, in retrospect, I’d have been better off turning down.

So be it. At any rate I’ve kept learning, about writing, about television and film, and most importantly about people. And the more capacity you have to understand people, yourself included, the more you’ll be able both to work with them and to create fully realised characters to put at the heart of the stories you want to tell. It’s their distinctiveness that will give your script its edge, even if you’re working in a genre where writers get away with two-dimensional characterisation. You don’t have to make the same mistake that they chose to perpetuate.