This week a Norwegian government commission into the killings of 77 people by Anders Breivik on the island of Utøya concluded that, with better communication and organisation, they could have been halted by the authorities before so many died. Tobias Manderson-Galvin’s play, which tries to worm inside the head of Breivik, underlines that lack of preparedness in a chilling imaginary scene: two smilingly unconcerned policeman paddle their canoe towards the island to investigate reports of an incident. They see what they initially think are swimmers enjoying themselves; it takes more than a minute to realise that the swimmers aren’t waving, but dying.

The Economist is very much a fiction, but one grounded in facts. It tells the story of a character called Andrew Berwick, but draws strongly on Breivik’s diaries, his 1,500-page manifesto, his activity on social networking sites and various interviews. Although he’s played by a smiling woman, this is clearly Breivik in all but name, and the six singing, fresh-faced young people in red sweatshirts certainly represent an idealisation of modern Norway.

Some may question whether making a song and dance about an atrocity that’s still so recent is justified. But the production isn’t prurient; it tells us little that’s not already available in the public sphere, and, in fact, offers some insights into a man who sees himself as a political martyr (“I am the saviour and the saved,” he says at one point). It follows Berwick’s progress from a 16-year-old arrested for graffiti, through his rejection for national service, and his retreat into a world of video games, internet chatrooms and fantasy – not the making of a monster, but something that tells us about the composition of Norwegian society itself. There is a telling moment towards the end when a Kurdish restaurant owner opines: “He was the nicest Norwegian I’ve met in 14 years here.”

Ultimately, the show’s jauntiness undercuts its seriousness, and it is easy to accuse it of forgetting the people who matter: the victims. But it’s also a reminder that while we would like to comfort ourselves with the idea of the mad loner, the Breiviks and Berwicks among us are made, not born.