"How did I end up here? .... Seriously how the fuck did I end up here," Mary Kate calls out to a packed out audience, as Walk For Me begins, and then again when it ends.

All I know is that, whatever about Kate, I'm glad I did.

In a spoken word monologue verging on rap, Mary Kate brings us through the highs (both literally and figuratively), and the lows of her life – from Catholic school and underage discos in South Dublin all the way to the belly of the beast working as a singer in the underworld of New York City – with no loss of style or substance at any stage of what is a challenging and invigorating journey.

The acting, as one might expect of such an experienced performer as Kate Stanley Brennan, is excellent. She delivers each character so well that I often found myself forgetting that it was, in fact, a one-woman show. The writing, however, is genius – all the more impressive for the fact that this is her first written piece put on the stage. More like poetry than dialogue, each sentence is masterfully crafted with the rhythm of its predecessor in mind, making the story flow effortlessly.

Substance is something that's often difficult to blend with humour, yet Walk for Me, hilarious at times, devastating at others, manages to work that magic superbly. The 'Wezz' section – about the legendary and sometimes notorious Wesley school disco on the south side of Dublin – was a shot of nostalgia for most of the audience, and Brennan's take on its inhabitants rang remarkably true. Meanwhile, I had a lump in my throat – I don't think I was alone – as Mary-Jane described her first sexual assault in the passenger seat of a car, and came to the conclusion "maybe that's why I said 'yes' all those times before. At least then I was in the driver's seat." This play does not shay away from difficult moments.

On the tech side of things, the show is a masterclass in what's achievable in live theatre, musically and visually. The beats dropped by DJ handsome Paddy were the perfect backing to the story, but when Brennan performed, whether as Mary Kate or taking on the persona of KittyKat, it felt like we were transported to a concert. 'Bad Girl' and 'Walk Alone' were particular highlights. The final number 'Just Be' had the whole audience on its feet, and fully in sync with the message at the heart of Walk for Me.

Meanwhile, the motion graphics on the screen behind multitasked as virtual props, backup dancers and signifiers, never stealing the focus from, but rather embellishing, the main story. Mention must also be made of the inspired costume changes throughout. Who knew one neon tracksuit could provide such a multitude of looks? With a quick tie here or fold there Kate achieved about five different looks before I began to lose count.

Overall, Walk for Me is an innovative piece of contemporary theatre, telling a gripping story and pushing the boundaries of live drama.

"How did I end up here? .... Seriously how the fuck did I end up here," Mary-Kate called out to a packed out audience as Walk For Me began, and then again when it ended.

All you need to know is, you'll be glad you did too. Go, now...

• Walk for Me runs until January 26th at the Project Arts Centre.