Young, gifted and jobless

The lack of parts for black actors led Nathaniel Martello-White to take matters into his own hands. The result is a new play, Blackta

Forward-looking: Nathaniel Martello-White (Richard Mildenhall)

I grew up on Brixton Hill, a child of Thatcher's Britain, in the Eighties. As a young black guy in south London there are many expectations of what you might become, should become or, sadly in a lot of cases, don't become.

I was very fortunate in that I came from a tight family of mixed-race heritage and had a mother who told me that anything was possible. Beautiful but dangerous words to say to a young upstart.

Growing up, I learned quickly that people are scared of difference. When you don't conform to what is expected of you people are quick to attack your individuality: Why * dressing like that? What music r * listening to? Why aren't * visibly strong and grunting like an ogre? Where's your hood?

In my late teens I became quite disillusioned with this kind of ignorance, and one afternoon was compelled to write my first street poem – "regular ting". I'd never written anything before, but it just poured out of me:

"I heard on the news Brixton getting trendy – the middle classes are opening all types of bars. Yeah we got bars too, but ours are metal and we got cages you can stay there for ages – just commit a crime – or try and survive. I been in twice now, if I go in again my mum's kicking me out – But that's ok, that ain't a thing coz where I live, that's just a regular ting."

It was a homage to the double consciousness experienced by a lot of young black men as they struggle to define for themselves what masculinity really is, what it means, reconciling all of the pressures that come from the outside world with their sense of self.

Cut to six years later, I'd graduated from Rada and was sitting in the bar at the Curzon cinema with a group of actor friends. One of the guys shared a story of how he had told another actor about a role he was playing in a TV drama. He said: "Oh, you're playing the blackta part. You know, the friend to the protagonist, the sidekick".

We all burst out laughing but there was something in it that was all too familiar. We were a group of actors who had come out of the top drama schools and played lead roles for the RSC and National Theatre, but now we found ourselves in a strange limbo. Why weren't there quality parts for us in TV and film?

And that's where Blackta started. From that laughter and then the creeping suspicion and frustration that the playing fields aren't level. Among my group of friends we would often find ourselves auditioning for the same part – and with depressing frequency that part would be the drug dealer or the guy-done-good from a broken home.

Another time, I'd bagged a lead role in a Second World War movie, had my bag packed and was ready to leave home, only to be told by my agent a few days later that they'd written out the part, because the marketing people claimed that there were no black American soldiers in the Second World War.

Around the same time, I'd been writing a lot of film scripts and not really getting anywhere, and a friend of mine said: "Why don't you write a play?". I went home and once again, it just poured out of me.

In a frenzy. A 17-page scene in one burst. Blackta isn't just a play about being an actor. Yes, the characters in my play are actors and are competing in something like an audition process, but on the simplest level it's about a group of guys in a competition where there is only one prize and no such thing as a second place. It looks at what those conditions do to their friendships. How friends become frenemies, if you like.

It is also a snapshot of some of the high highs and low lows of being a black actor. It comes from my conversations and frustrations, it revels in the absurdity and the sheer joy of being an actor. I wanted to write a play that I would want to watch at the theatre; I didn't want it to be preachy or whiny. The characters in my play are obsessed with winning, at any cost. It is an amplified, ramped-up version of the competitiveness I saw develop between friends when they realised that they were battling for the one seat at the table.

There is this thing in black communities, a kind of post-colonial syndrome, where people are defined by how fair or dark they are, how soft or tough their hair is, how light or dark their eyes are, how fine their features are. I wanted to get close to this, so I decided to set the play in an abstract world and not give the characters names, but shades – Brown, Black, Yellow, Dull Brown. It allows me to explore the caste system in black communities, which essentially boils down to how much or little white blood is in your heritage.

Sitting on the other side of the desk during auditions was brilliantly strange. Auditioning actors and asking them what they made of my script was terrifying. Pretty quickly I started to hear feedback that they had had the very same conversations as I had. What struck me as tragic was that actors in their 50s and 60s told me that they had felt like this for years, too. Damn, will the next generation be stuck here 20 years from now?

If there is one key idea behind Blackta it's the idea of self-mobility. If life doesn't open the door of opportunity for you, it's up to you to create your own thing. For me, it was writing, but some of my peers have gone into directing and producing their own material. It has to go further than this: a collective frustration among black actors in the UK about the limited roles we are offered means that many are making the tough decision to relocate to America (three of the cast of Blackta are going next year).

We can't end up in a situation where all of our best talent is lost. I'm part of a generation who believes that they have a rightful seat at the table. A fiercely talented and intelligent generation of black British artists, writers and actors who want to express themselves with material that not only reflects their complexity but also their eloquence and talent. That stretches beyond the realms of the tower-block estates. London should be a benchmark for the world.

'Blackta', Young Vic, London SE1 (020 7922 2922; youngvic.org) from 26 October to 17 November