A circular turquoise paddling pool marks out the scene. This colourful pool is empty, the better to represent a cheerful reimagining of the dull dancefloors on which entrants to Blackpool’s famous competitions pray for salvation from the judges. As the lights come up, ballroom music blares and two robust-yet-elastic performers wade in.

It takes a while to work out where this high-tempo tornado is going, but the thrill of the chase is worth keeping up with across the course of what seems like a cathartic experience for its stars. Milla Virtanen and Jaakko Toivonen have travelled extensively to research the history of their art, and Blackpool is these Finnish dancers’ homage to the world of professional dancing and its dark underbelly.

With ghoulish glints in their eyes, the pair dissect the artificial sheen and cruel intensity of ballroom competition, occasionally accompanied by the reading of scores in a matter-of-fact voice from the darkness. Whether they’re being marked up or damned by these invisible judges, they plough breathlessly on, seemingly imprisoned by the need to keep smiling and dance.

Toivonen, whose arch showmanship and dynamic flair carries something of the Eurovision bombast he cherishes, flails a leg over the side of the pool, drawing unsettled laughter from the round. Both dancers, they later tell us, competed at Blackpool as teenagers, and the autobiographical parts of their performance aren’t shy to recall the more harrowing moments from those contests.

At one point, Toivonen slumps forlornly against the edge of the sphere for a sombre rendition of Bruce Springsteen’s ‘Dancing in the Dark’, and crashes, sprawled face-down, centre stage. Virtanen, meanwhile, is a three-time Finnish champion in Latin American couple dancing, and even for the most untrained of onlookers the Latin sections of the piece brim with flair, all staccato posturing within spaces the span of a telephone box.

A purely joyful, glittery sequence set to Donna Summer’s ‘I Feel Love’ is glorious. Predominantly, though, you feel a real sense of the lasting scars rendered by endlessly repeating the same demanding moves in the face of unforgiving assessors and world-class opposition.

The shadow of fierce criticism hangs in the air, and there’s a little of that horror for the crowd, too: audience participation is a terrifying part of Brighton Fringe at the best of times, but the folks Virtanen and Toivonen invite to the floor must feel particularly overwhelmed by the action taking place around them. Despite the ravages of a discipline hellbent on perfection, Blackpool has the grace to dance out an affectionate – if discomfiting – memoir.

The Old Market, until May 25th 2018. 9.30pm, £10.50/£8.50. Book tickets. Part of Brighton Fringe’s Finnish Season.