In 1937, a businessman called John Rabe sheltered a quarter of a million Chinese civilians from the Nanjing Massacre, a defining atrocity of the Second Sino-Japanese War. But Rabe was a German businessman, a member of the Nazi Party, so while he’s celebrated as a hero in China he was shunned by the Allies in Europe. In Chestnuts, a man called Teddy begins to read Rabe’s diary while he considers leaving China to return home to the UK. Teddy is queer, as is his flatmate Polly – and they’re both mourning friends who died too young.

These are all big themes, and you can’t fault the ambition in Yuner Chen’s script, but it’s not clear how or whether they relate to each other. Teddy and Polly live in Shanghai, not Nanjing, and if Rabe’s story is meant to illuminate their lives I’m afraid I didn’t see how. The backstory is busy too, with a network of relationships and major life events that aren’t explained until relatively late in the script. Building curiosity by withholding information can be a highly effective technique, but here the weight of unresolved references becomes overwhelming.

That overcrowded feeling seeps into the direction, too. Some scenes are elegant, even beautiful – the candle ritual that greets us as we enter is striking and charged. Others hit a witty and almost surreal note, with Rabe appearing in the guise of a flight attendant, while yet another is a dance-like depiction of dressing for a wedding. At the very end we suddenly find Teddy and Polly hosting a YouTube channel, which appears to be long-running but hasn’t been mentioned before. Each of these concepts could work well in isolation; together they grow discordant.

There are ideas here that deserve sharper focus. Rabe increasingly forces his way into Teddy’s imagination, and there’s interesting ambiguity about exactly what he represents: is he literally a ghost, a diary given voice, or a projection of something from Teddy’s own psyche? And while we learn enough about Chinese history and culture to lend context to the play, the difference in attitudes to Rabe remains relatively unexplored. The balance of the narrative skews clearly in his favour; perhaps that’s justified, but even if so, the tension inherent in the idea of a “good Nazi” calls for closer study.

Less can be more, and Chestnuts is loaded with enough conceptual cargo for two or three Fringe-length plays. My advice to this young company is to believe in their future: opportunities to tell further stories will surely come. For now, focus on one big idea, one telling metaphor, one intriguing mystery, one visual style. And I’d begin by clearing more space for the ghost of John Rabe – for that story poses questions that are genuinely haunting.