Every once in a while, you are in the fortunate position to see something which makes you want to place your hands beneath the feet of the theatre makers and thank them for bringing that story into your life. The Strange Undoing of Prudencia Hart is such a story.

Told in the form of a theatrical ballad (rhyming couplets and all), The Strange Undoing of Prudencia Hart is the tale of a buttoned-up Scottish PhD student whose topic of study is the Border Ballads. At a winter conference in Kelso, she gets thoroughly dressed down by the members of her tribe (other academics, always eager to see one of their own fall into the pit) before discovering her car is snowed in and she must spend the remainder of the evening in the company of her least favourite person, Colin Syme, a poststructuralist with a Kylie Minouge ringtone who favours using the word "ethnographic" for profanity. 

And then it turns out to be not just any old winter evening but Midwinter's Eve, a time for strange encounters – only some of which are precipitated by copious amounts of drink, sudden karaoke, and very, very red lipstick. Others... well, others arise from stranger concatenations of circumstance and have even more profound effects on the psyche than the above.

Strong on plot and witty of rhyme, The Strange Undoing of Prudencia Hart could easily be appreciated for the text alone. It also deserves top marks for costumes, staging, music, and, most of all, the performances. Able to produce powerfully evocative images with limited props and a few simple costume changes, this is everything that a small, mobile theatre company should be. Hats off to writer David Greig, director Wils Wilson, designer Georgia McGuinness, musical director and cast member Alasdair Macrae and movement director Janice Parker for crafting such a beautifully adaptable production.

The cast are riveting as they move over, under, around and through the space, including on the tabletops in front of us and even on the bar. You never quite know where they will be off to next. The show opens with the cast en medias folk tune, as Prudencia would never be caught dead saying. Melody Grove plays Prudencia with passion, grace, and wit. Her almost-nemesis Colin Syme is endowed with a slick sly humour – but underneath, a great whacking dollop of heart – by Paul McCole. David McKay's Nick (Old Nick, that is) is by turns terrifying, enticing, infuriating and poignant. He shares the role with McCole who adds his own layer of devilish humour. Annie Grace gives an ethereal performance as the singing Woman from the Estate, who remained in my mind's eye long after that brief scene ends. Alasdair Macrae has a gleeful twinkle as Chairman at the conference and general master of mischief throughout. All of the cast except Grove also take various enchanting turns as drunken pubgoers, simpering academics, bullying harpies, and faltering singers of Bob Dylan songs. 

I was very impressed by the physicality in the show: the cast formed Prudencia's car driving down the road and Colin Syme's motorcycle with his scarf flapping behind him in the breeze. The Four Corbies' exaggerated hangovers left absolutely no doubt about the happenings of the previous evening. Prudencia and the devil shared an elegant and witty three-way dance in the second half expressing the futility of trying to escape what one is simultaneously attracted to and repelled by. But in the end no matter how many tricks and twisty shapes the devil tries to employ to ensnare her, there's only one Colin Syme (sing to the tune of "Guantanamera".)

On the set design front, the crystal sherry glasses used as bells are pleasingly resonant, the dextrous employment of flashlights and candles to subtly alter mood and perspective made me smile into the darkness (the sound design is also very effective on this front), and the snow – which the audience is tasked to create before the show begins – is, of course, sublime.

Costume-wise, gorgeous as it was I didn't envy Prudencia's heavy green felt cape on such a muggy evening (if you do go, bring a fan. London Welsh Centre's upstairs space is a brilliant complement to the show, but very hot.) The Four Corbies in their sparkling masks are a monstrous treat, as are the varied incarnations of Old Nick including a rather natty eye-covered jacket evoking either the demon Argos Panoptes or one of the angelic Four Living Creatures, depending on how you look at it. A simple white bathrobe made the Woman from the Estate look like an angel.

Sometimes it takes you an eternity to discover that your song was within you all along. And that's okay, because finding your song is the only thing that matters. The Strange Undoing of Prudencia Hart is astounding on all levels. Long may it run.

In sum, why are you still reading this review? Go out and get some tickets!

The Strange Undoing of Prudencia Hart, at London Welsh CentreCaitlin McDonald reviews The Strange Undoing of Prudencia Hart at the London Welsh Centre, part of the Royal Court's Theatre Local.5