Camp Siegfried is more than a German-themed summer camp for German Americans in 1938 Long Island; alongside all the usual fun activities, Nazi doctrines are openly pedalled.
The camp is based on a real Camp Siegfried, which operated in the 1930s and included flower beds in the shape of swastikas.
Bess Wohl's play sets the innocence of a teen romance against a backdrop of fascist grooming.
Our teenagers, played by Patsy Ferran and Luke Thallon, are in the process of finding out who they are and what they want out of life. They are impressionable but without realising it.
Thallon's Him is 17 and already fully immersed in the camp and its values, having visited several times before. He spots Ferran's Her, a shy 16-year old and makes a bee-line towards her.
It's her first camp, she's there with an Aunt and not finding it easy. The marching bands are loud, she doesn't like dancing and is no good at sports or anything outdoorsy.
Romance is encouraged
As the two hang out together more and more, we learn of how 'romance' is encouraged to further the Nazi cause and, through camp gossip, how the reality is often inexperienced fumblings and embarrassment, not the great love and conquest most anticipate.
It is one of a trickle of reminders as to how young Him and Her and their fellow campers are and makes the idea behind the camp all the more shocking.
Romance between Him and Her begins to blossom, awkward at first but slowly growing in surety. It fuels their self-confidence while Camp Siegfried in turn offers an identity, a cause to feel part of. It's a sense of belonging.
But all good things - even Camp Siegfried - come to an end. Is it just a fleeting summer romance - with each other and the Nazi ideology?
What Bess Wohl's brilliantly written play does so well is to weave the humour of a teen logic and love with the serious events of the day when the world was careening towards war.
Parallels with events today
You can't help drawing parallels with today's radicalisation programmes and, in particular, the teenage girls who've travelled from the UK to Syria and ended up married to ISIL fighters.
The innocence and confidence of youth are beautifully brought to life by Ferran and Thallon.
My only disappointment in what was a highly anticipated play was the fact that they spent so much time in a stage blind spot, so there were chunks where we could only see one or neither of the actors.
Our seats were in the Royal Circle on the side, where you expect the actors to flit in and out of the corner of the stage you can't see from that angle, but they don't move around a lot.
It was annoying because you didn't get to see the body language, which is so much part of the performance. This was a preview performance, and it is something easily remedied by moving the actors closer to the centre of the stage, which I hope they do.
Camp Siegfried is 90 minutes without an interval, and I'm giving it four and a half stars. It would have been five if I'd seen the whole thing.
For more information and tickets, visit the Old Vic website.
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