Josephine's story, writer/performer Caroline Horton cautions us at the beginning of her play Mess, is "complicated and long."

Long, not so much — the show, originally a hit at the 2012 Edinburgh Fringe and now running at Manitoba Theatre for Young People, is a compact 70 minutes.

Complicated, yes — as any story about living, and fighting, with anorexia must be.

But it's also riveting theatre in this remarkably creative and utterly unflinching show for teens.

Based on her own experience, Horton's play tells the story of Josephine, a 20-something plagued by anxiety, who attempts to exert some control over her world by strictly regimenting her eating habits. Gradually, terrifyingly, that morphs into anorexia as her irrepressible friend Boris (Hannah Boyle, delightful when she's not heartbreakingly tragic) watches helplessly.

Yes, this is a play about "an issue," but it avoids moralizing and cheap sentimentality. And while it may spare some of the more gruesome physical descriptions of anorexia, it's unwavering in its probing examination of the psychological and emotional realities of the illness.

It's also funny. Often very, weirdly funny, and not at all what one might expect in a play dealing with an issue that is, quite literally, deadly serious.

Horton has wrapped Josephine's story in a fascinating, meta-theatrical package.

Josephine tells us she and Boris, along with Sistahl (Seiriol Davies) — who acts as accompanist, narrator and sound-effects man — are going to act out her story. But the big-budget "real thing," she frequently reminds us, will be much grander in scale.

That, and the tasteful and brief musical numbers sprinkled throughout, have the effect of reminding us that we're watching a story. But its vibrant emotional core also never lets us forget that in essence, if not in every detail, it's all too real.

The convention also lets Davies, as the slyly winking Sistahl, provide plenty of comic relief, with everything from goofy sound effects to quietly exasperated exchanges with Josephine as playwright/director.

Caroline Horton in Mess at MTYP

Though it deals with deadly serious subject matter, Mess is often surprisingly and weirdly funny. (Edmund Collier)

That's a tricky tonal balancing act to pull off. Mess often makes hairpin turns from comedy to harrowing tragedy, and from utter silliness to horrible stillness. But Horton's polished script pulls it off, as does the talented trio of performers.

Mess avoids easy answers. There's no pat happy ending here — anorexia is something, Josephine suggests, that she can learn to live with, but not something she'll ever live completely free of.

It's not an easy journey. It is, in fact, downright messy. But it's also, in its own unique way, beautiful.

Mess runs at Manitoba Theatre for Young People until Feb. 26.