Brother and sister Pepíek and Aninku are too poor to buy milk for their sick mother. They sing for money in the streets but the evil organ grinder Brundibár – who bears more than a passing resemblance to Hitler – chases them away. But with the help of the town’s children and some fearless animals, they overcome Brundibár and sing joyously together in the market square.

Brundibár is an opera for children, written in 1938 by Jewish Czech composer Hans Krása as the Nazis spread across Europe and were threatening Czechoslovakia. Records suggest that Hans had been transported to Theresienstadt concentration camp by the time of its first performance, in Prague in 1942 by the children of the Jewish orphanage there.

But, in what could be taken for the plot of a dramatic play in itself, the score of the opera was smuggled into the camp – where almost all the children and the staff from the orphanage themselves ended up by 1943 – where Hans re-orchestrated it for the various instrumentalists who were available to play at the time, and Brundibár was performed 55 times by the children of the camp, including in a Nazi propaganda film and in a carefully staged production for the Red Cross.

But real life didn’t reflect the opera’s playful and uplifting message of music and art winning out over evil – heartbreakingly, Hans had to recast the children’s roles several times over and, shortly after the propaganda film was finished, most of those involved in the production were transported to Auschwitz and murdered, in October 1944.

“When you watch the show you catch yourself imagining what it must have been like performing it in incredibly difficult circumstances,” says Frederic Wake-Walker, who is bringing Brundibár to Watford Palace Theatre this weekend, with Mahogany Opera Group, based at the Palace, and children’s opera company Jubilee Opera. “It brings a whole new level of poignancy to your experience of the piece.

“A ghost occasionally appears and just touches you on the shoulder.”

The production sees professional opera singers, provided by Mahogany, perform alongside children local to each of the venues it visits, as part of Jubilee’s ethos of providing opportunities for young people of all backgrounds to participate in performances of opera. The children in the Watford production are mainly from Hemel Hempstead and got involved via Hertfordshire Music Hub.

Director Frederic believes the opera has a strong message for children today, both those in the opera and those watching it.

“We’re not putting on a museum piece, it’s not just about remembering Brundibár’s past, although I don’t think that story can ever be separated from the opera itself,” says Frederic. “It’s very much speaking to kids today, saying that if you come together as a group then you can be more powerful than if you try and fight evil on your own.”

As the children performing Brundibár today and the opera’s unlikely survival of the horrors of the Holocaust both attest, it seems that maybe the joy and beauty expressed in music and art can outlast evil after all.