Our rendezvous is the information centre on the edge of Holyrood Park. We’re there to meet the legendary pun-loving archaeologist, Dr Grones (geddit?), and his fresh-faced sidekick Milo – and then together, we’ll head off on an adventure. This fun interactive show uses the park as its stage, and soon we’re following Dr Grones as he strides past lochs and crags, cracking out his compass and his magnifying glass in the name of old-fashioned derring-do.

The storyline isn’t life-changing, but nor is it meant to be. There’s a fabled treasure, a deadly rival giving chase, you know the sort of thing. There are a couple of surprises waiting to be sprung, and some clever use of the park’s features; one memorable scene sees the two adventurers shouting at each other across a road, in a knowing echo of countless films where the heroes are separated by a gaping chasm.

Along the way we tackle a trail of clues, each revealing the route to the next stage of our mission. Although their phrasing is mildly cryptic, the clues are essentially observation tests – and there’s plenty of opportunity for light-hearted competition to be the first to spot the crucial feature or sign. Our archaeologist hosts work discreetly to keep the story moving along, helping out with the clues as needed and leading the way between scenes; there’s an invigorating sense of urgency, but the feeling is more dynamic than rushed.

A couple of practicalities could use some review. Though most of the walk is on good and gentle paths, the final stage does include a relatively steep uphill climb, which limits accessibility for less agile adventurers without huge storytelling gain. The end-point is also unexpectedly some distance from the meeting-point, which isn’t ideal in the tightly-scheduled environment of the Fringe. If this show returns in the future – and I hope it will – I’d suggest extending the advertised running-time, to allow for the 20 minutes or so it takes to return to the start.

What makes the walk worthwhile, however, is the quick-witted humour of the adventuring pair, who are more than happy to engage in off-script banter with their audience. Andrew Agress, as Dr Grones, is intense and resolute (just as long as there aren’t any snakes), while Connor Wahrman’s Milo is filled with nervous energy. It all adds up to a loving pastiche of a well-worn genre, which still develops a worthwhile plot of its own. And my goodness, how lovely it is to escape the stuffy theatres, and enjoy a few lungfuls of laughter out in the open air.