Showing @ Assembly Roxy, Edinburgh until Sat 22 Mar (touring)

After having toured nationally and internationally, David Greig and Wils Wilson’s lock-in ballad returns to Scotland. Expert in folk music, the traditional and opinionated Prudencia Hart (Melody Grove) is invited to speak at a lecture in Kelso but upon returning to Edinburgh, she finds her car in need of avalanche rescue. Stuck with her pseudo nemesis, the disdainfully modern and crass fellow academic Colin Syme (Paul McCole), the pair attempt to enjoy a singsong in the pub and find somewhere to stay.

The bounding rhythms of Greig’s lilting script give it an air of the border ballads Prudencia’s so passionate about. Stylistically, the use of rhyming couplets adds to this but when coupled with the snow, the plot’s peculiarities and the live music, there’s a strong whiff of fairytale. This is magnified by the looming walls of the Assembly Roxy’s ancient masonry, bouncing the bursts of Celtic harmonies around the audience like surround-sound speakers.

Greig’s cartoon like characters are emphasised by Wilson’s frenetic direction. The cast roam about the room of eyes, clambering onto tables or plonking themselves into laps, sweeping you into the story with the drifts of white tissue. This ensnaring of viewers mirrors how folk song’s pull listeners into stumbling along with their own particular tale. Being site-specific brings inventive staging – Prudencia’s marvelous car of two torch headlights and a violin bow windscreen wiper – and this unabashed creativity feeds into the folkloric atmosphere.

Not that the show is all wanton whimsy. Along with comments on professional women’s struggle in a man’s world there’s a strong sense of old versus new, musically depicted when the folk evening switches into a wonderfully garish karaoke night of drunken pop masquerade. Clad in a green cloak and balking at Colin’s Kylie Minogue ringtone, Prudencia is an anachronistic thinker split between the time of those she studies and today. Like A Christmas Carol, Greig’s play covers the past, present and future, asking us to consider along with Prudencia the implications of them all.