Measure for Measure to music

West Side Story, Kiss Me Kate, even The Lion King – all have shown us how Shakespeare’s stories can translate into musical form. It’s not hard to see why: the plots provide strong frameworks for adaptation, with central problems to be resolved, protagonists for us to root for, villains to charm us, lovers to pity – they're all there.

Although Measure for Measure is often referred to as Shakespeare’s problem play, its translation into a musical set in Soho in the 1960s feels – perhaps surprisingly – right.

Desperate Measures looks at a time in our history when censorship regulations were loosening, when a generation of free love and sexual liberality burst onto the scene, and asks the question: "What if it had gone the other way?" What if the government had decided to crack down on lewdness and brought back a sexual congress act, even the death penalty? It’s not so hard to imagine.

Pitching Isabella/Isobel can be difficult: the poor girl goes through so much over the course of the play!

Ultimately the story of Measure for Measure is timeless, as at its heart lies an absolutism, an unwavering faith, one which can be found all over the world today. You can't open a newspaper without reading about another example of an extremist act brought about by a straightforward, black-and-white belief that one person holds, which cannot be questioned – it just "is". Both Measure for Measure and Desperate Measures centre on two characters who ultimately believe in a higher power, without doubt, and it is this unfaltering belief which drives their journeys through the show. They may manipulate their belief to benefit themselves or question why they are being tested, they may even feel abandoned, but their belief that a higher power exists never falters. So whether you're performing Shakespeare’s text or a new musical based on the same events, that central theme of absolutism remains and gives the play its relevance.

Musically, Desperate Measures is a gift for its actors. We're given such a vast range of music – the audience can expect a smörgåsbord of styles. Each song drives the mood and plot forward, to the point that it becomes intrinsic to the show, working symbiotically with the book. At first the show has an awareness of its own musicality, paying tribute to the popular music of the Sixties, but as the plot progresses the music begins to flow organically from the dialogue: as the stakes build, song becomes the natural medium through which the characters can fully express themselves. The challenge for the actors will be maintaining those stakes and earning the right to burst into song. It’s such an exciting piece to perform: it twists and turns from humour to heartbreak again and again, and having a cast of 13 actors in such an intimate space lends an incredible energy to the show.

The challenge I've found as an actress playing Isobel/ Isabella is in stamping out my own cynicism and finding a simplicity in her nature rather than an anxiety. In our world of reality television there is a phoniness which pervades our lives, which can make us all a little cynical (or a lot), but there’s no place for it in her world. Pitching Isabella can also be difficult: the poor girl goes through so much over the course of the play! The stakes are so high for her from so early on that it can be difficult not to burn out, or come in too hysterical and leave yourself with nowhere to go. I was so inspired by Anna Khalilulina’s performance as Isabella in Cheek by Jowl’s recent Russian production of Measure for Measure. Her performance was so astonishingly raw and stripped back, so beautifully judged. There is a humour and sort of lightness to parts of Desperate Measures that mean screaming on the floor and ripping at your hair would feel a little out of place, but the honesty of Khalilulina’s performance has certainly acted as a sounding board for me during rehearsals. Besides, the role has always been something of a dream of mine, with a surname like Nunn…

Desperate Measures makes no claim to be an improvement on Measure for Measure. However, it does lend an accessibility to the story and central themes of the play which I hope audiences at Jermyn Street will enjoy as much as we have enjoyed creating it. Now, I’m off to look for a wimple.

• Ellie Nunn stars in Desperate Measures at the Jermyn Street Theatre from 24 November to 20 December

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