You cannot move at the Edinburgh fringe for circus shows. There are so many people in this city who can climb a rope, hang upside down, swing on a trapeze – so how do you make a show special when plenty of other folks are hawking the same skills?

Melbourne company One Fell Swoop Circus have worked out a way, sprinkling a bit of magic on their festival offering. It’s a show that was originally made a decade ago, but had its Edinburgh debut last year and was such a hit that they have brought it back. Like many of the best shows, it’s really just one good idea, with all the juice thoroughly squeezed out of it across the course of an hour. That idea being: one giant rope, two pulleys, seven bodies, and everything they can do together.

Group hang … By a Thread. Photograph: Jane Hobson/Shutterstock

Looped from the ceiling, the rope becomes a slackline to walk across, a trapeze to swing on, a vertical climb, a diagonal slide, and so much more. It’s all gently paced with a dreamy mood, but steadily engrossing, the soulful soundtrack slowly casting a spell. The skills are a given, but it becomes a great piece of theatre when the performers’ personalities start to emerge – the mechanics of the rope plus the dynamics of the group, that’s what is interesting.

Plus there’s their individual skills, like Ellie Grow’s mind-blowing handstands. She’s more secure on two palms than most people are on two feet, which means she can turn what could be a quick trick into choreography, with rhythm, timing and wit. Then there’s a beautifully tender duet, multiple metres up in the air, that’s not really about acrobatics but human connection, hands and eyes meeting, warmth and friendship, all subtly done. The emotion feels real, and the tone is perfectly judged. Ropes aside, that’s what really elevates these acrobats.

• At Assembly Rooms, Edinburgh, until 30 August. Then touring

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