Do writing competitions matter? They certainly do to 26-year-old Ben Musgrave. He’s just won the inaugural Bruntwood playwriting competition, beating more than 2,000 rivals to a £15,000 prize and a four-week run at the Royal Exchange.

Musgrave is the youngest writer to have had a play staged in the theatre’s main house. And sometimes it shows: Pretend You Have Big Buildings is both driven and dragged down by its welter of ideas about identity and ambition. It’s stimulating and likeable, but it’s punching above its weight on a big stage that exposes its storytelling contrivances.

Romford, 1994. Teenager Danny (Sacha Dhawan) arrives from India with his mother Ruhksana (Shobna Gulati), moving into the house left to them by his recently deceased English father. He’s first assaulted by, then befriended by, Leon (Jonathan Bailey), a local lad with a taste for dressing up in his mother’s silk nightie. My Beautiful Laundrette for the 21st century? But that’s just the start of it.

Leon’s parents aren’t getting on. Blokey, affable, racist Rob (Steve North) wants to turn down the redundancy deal he’s being offered at the car factory. His upwardly mobile wife, Karen (Tanya Franks), wants him to face facts. Canary Wharf has just been switched on. It blinks over the area to remind them that they are all in the shadow of the City: manufacturing is retro, the service economy is here to stay.

Unfortunately, Musgrave’s sociopolitical themes are writing cheques that his characters can’t yet cash. Danny morphs unconvincingly fast from naif to brittle, glottal-stopping tearaway. His mother flits between stateliness, pining and irresponsibility. We don’t get a proper sense of where they are from – and the way both actors’ accents tend to revert to their northern roots doesn’t help.

Too often the protagonists live not in Romford but on Planet Playwright. They race to air their innermost thoughts, sometimes direct to the audience. There’s too much happening for this ever to be dull: Jo Combes and Sarah Frankcom’s production is slick and atmospheric, with furniture gliding in and out of the bare stage. Yet there’s no time for any of the component parts to quite convince. “Was it rough? Was it racist?” Ruhksana asks of her boy’s first day at school, knowing that this is the kind of play where you need to get straight to the point.

Still, it’s the job of first plays to overreach themsleves. There are enough insights and sketches of characterisation here to make you think that Musgrave has a bright future, once he tightens his focus. You can see why Pretend You Have Big Buildings won its prize: it has a scope and a sense of recent history that too many new plays lack. But onstage its dramatic flaws are shown up. Too many ideas, sometimes, can be worse than too few.

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