Squidink Theatre’s interpretation of Shakespeare’s Romeo and Juliet is the kind of production that makes reviewers nervous. Promotional materials, including the terse, polemical director’s message in the programme screams that this is a piece of self-conscious théâtre engagé: it is inspired by the charity Acción Interna, whose admirable work in Colombian prisons makes the production worth supporting in its own right. Predictably, there are plenty of bold directorial decisions for the audience to murmur about: the cast is all-female, the action takes place within, amusingly, “HM Prison Verona”, with the central dalliance taking the form of an inter-gang lesbian relationship, and there a feeling that the play functions as a sort of critique of austerity. Pleasingly though, the black turtlenecks have been rolled down just far enough to reveal some genuinely brilliant acting, and a remarkable turn from Lucy McIlgorm as Mercutio will go a long way to silence anyone who still treats all-female Shakespeare productions as a passing fad.

The pioneer of modern gender experimentation with Romeo and Juliet was the American actress Charlotte Cushman, whose 19th century tour of the United States as Romeo to her sister Susan’s Juliet was facilitated by her gruff contralto register. Lorelei Piper, however, is a different kind of female Romeo: she does not seek to ape an absent masculinity, but rather reimagines Romeo as wholly female, a decision aided by some sensitive pronominal tweaks from Director Conky Kampfner and Assistant Director Cesca Echlin. This means that the romance is lesbian, and this choice is immensely effective. If I have one criticism in this regard, it is that this aspect of the production could have been even more boldly expressed: the lambent tension of the balcony exchange is never quite realised in the sleepoverish post-coital scene.

Piper’s physicality elsewhere, however, is a delight: as the callow Romeo mopes over Rosaline, in love with the idea of being in love, she drapes herself languidly over a set of stairs as she laments that Juliet will “not be hit / With Cupid’s arrow; she hath Dian’s wit”. Though Romeo is somewhat swamped by her noisy coterie in the first two acts, Mercutio’s death in Act III makes room for a convincing maturation deftly rendered by Piper, whose quivering soliloquies give way to a moment of choking pathos as Piper’s voice cracks on the line “Then I defy you, stars!” One or two slips are likely to rankle only the most exacting bardolater, such as the pronunciation of “doth” to rhyme with ‘moth’. Less pardonably, however, some unfortunate sound design in the form of twitchy electronic muzak rather overshadowed some of Romeo’s most poignant soliloquies, so that during the death pangs of Act V, I found myself scribbling in my margin: “next week on Prison Break…”

In Juliet, Emelye Moulton is faced with an arguably harder task than Piper. Shakespeare’s adaptation of Arthur Brooke’s didactic poem still bears signs of contrivance, as the spirited wisdom of Juliet’s lines fights to reconcile itself with her tragic arc. For the most part, Moulton exploits this tension admirably: her understated, metrical delivery of the blank verse suggests naivety, while exposing the lucidity of many of her lines, as well as a hint of defiance as she resolves to “try” and love Paris. The conceit of prison life works well for Juliet too: Moulton’s trenchant pronouncement on “old folks”, for example, is aided by the implication that she might be some kind of young offender or new inmate.

Perhaps it is worth considering how successful this conceit is overall. The rather obvious substitution of a women’s prison for the oppressive norms of Veronese society is forgivable not just for its worthy charitable tie-in, but for the immense scope the setting affords for dramatic experimentation. The balcony scene is a masterstroke: rather than cooing to Juliet from below, Romeo stares down and across at her from a high gallery at stage right, with the stark iron railings of the Keble O’Reilly theatre redolent of an American-style multi-level prison. The gallery extends round to the circle, and as a result the audience is conscripted into the scene, forced into voyeuristic concert with Romeo as he gazes at his spotlit muse.

Matilda Granger’s set is a triumph of grey and white parsimony, perhaps as a kind of post-Luhrmann expiation, and can be credited as the source of many of the production’s most haunting images. Nowhere is this more apparent than during Romeo’s first encounter with Juliet in Act I: despite the conspicuous absence of tropical fish, the scene is poignant and visually arresting, with the actors lit in purple behind a diaphanous gauze screen and framed by banks of serried bars. Despite being at the geographical heart of the set, this intimate space is rarely used (with the jarring exception of a few extraneous pole dancers) and its reprisal in Act V as the prison morgue invites a moving comparison with Act I. Once again, however, a soundtrack is on hand to drag the exchange down to the level of bathos: having already forgiven an accidental salvo of laptop-derived bleeps, I was grateful when the Prison Break music mercifully gave way to silence; but this was soon replaced by a swelling piano number, which, rather like Romeo’s kiss, seems a little too “by the book.”

The other slight limitation of the patriarchy-as-prison conceit is that it collides awkwardly with certain subplots, notably that concerning Paris’ proposed union with Juliet. Kampfner and Echlin have made the interesting decision to reimagine Paris as a male prison guard, a choice which does pay some dividends: the Nurse’s exclamation that Paris is “A man, young lady!” is transfigured, while Capulet’s obliviousness to Juliet’s blossoming sexuality reinforces how Juliet’s forced marriage is a contravention of her very nature. However, there remains the question of why Capulet is seeking to “wed” the young inmate Juliet with the prison guard Paris. Still, this complaint is minor: if Kampfner and Echlin have sacrificed verisimilitude in favour of preserving Shakespeare’s coruscating language, they have made the right choice.

Piper, Moulton, Kampfner, Echlin and Granger all deserve individual praise, but Lucy McIlgorm’s Mercutio was the jewel of this production. McIlgorm manages speak the verse better than anyone else on the stage, with a buoyant clarity that carries the audience along through her brisk badinage with Romeo and Benvolio. The alacrity is infectious, and Libby Taylor’s sometimes staid Benvolio is most fun when playing off her boisterous pal. The switch to an all-female cast has done nothing to diminish the jocularity of the relationship, and this is largely thanks to McIlgorm, who delights in the bawdiness of Shakespeare’s dialogue. Ribald mimes abound – the famous line about “pricking” is accompanied by a gesture that brings a whole new meaning to the phrase “tongue-in-cheek” – and the surprising plausibility of this kind of humour in an all-female environment is a rich vein for any would-be gender theorist.

Does McIlgorm’s turn overshadow the rest of the troupe? Perhaps, in the first three acts. But this is as it should be: Mercutio is so compelling precisely because she is the arch humanist, who threatens to deflate the other characters’ grandiloquence. Her existence jeopardises the very ideas about fate upon which the tragedy depends, and this is the reason for Shakespeare’s perhaps apocryphal remark, prized by Stephen Greenblatt: “I had to kill Mercutio before Mercutio killed the play.” In any case, Director Conky Kampfner could not have hoped for a more captivating iconoclast than McIlgorm.

It is worth singling out a few other performances. Gaby Kaza is entertaining as the Nurse. The manic energy she brings to the role of go-between is refreshing, and her porcine snores from the bottom bunk interrupting Romeo’s passionate serenade are just one example of a collection of ingenious and genuinely funny responses to tricky stage directions. At times, Kaza’s exuberance, coupled with her perhaps unconscious impersonation of Nursie from Blackadder, undermines the pathos of certain scenes, but her unravelling at the death of Juliet is a devastating climax to a dramatic irony expertly cultivated throughout the scene. Imogen Edwards-Lawrence brings a turbulent physicality to the role of Capulet – pitched somewhere between Bernarda Alba and a sadistic PE teacher – that spawns some of the most convincing choreography of the production. Nancy Case understands the laconic humour of the Friar’s early lines, and exudes a kind of professorial equanimity until the play’s tragic conclusion. Other performances were slightly less polished: Jeevan Ravindran’s Montague and Dan O’Driscoll’s Prince occasionally had lines swallowed up by the imposing space, but this is the kind of hitch that can easily be remedied as their voices settle into the venue.

Squidink Theatre has not put on a perfect production. The sound design is perennially distracting, and there are a few inconsistencies in the Paris subplot. But what they have done is assemble a remarkable young cast, who, despite varying levels of experience, are all absolutely compelling in their enthusiasm for Shakespeare’s verse. They have more than vindicated the idea of an all-female production, and devastated the notion that Shakespeare’s verse rings true only for straight relationships. If there is one overriding message in this interpretation, it is simply that when we love someone, we do so regardless of their name, regardless of their crimes. And as I walked out of Romeo and Juliet into the warm evening, I realised that despite of all this production’s imperfections, I had loved it.