Ecstatic Arc[author-post-rating] (3/5)

Through the piercing darkness in the Library Gallery at Summerhall, a green and a red light can be seen glowing faintly. As lights of all shapes, sizes and colours flash around it accompanied by an array of booms and crackles, the Tesla Coil sat trapped in a cage remains silent. For around 15 minutes, the various steam-punky machines in Robbie Thompson’s Ecstatic Arc try their hardest to create an electronic concert together. Then the Coil comes along, buzzing wildly, putting everything else to shame.

This is installation meets performance, or rather installation in performance, as the objects placed around the room (open throughout the day) take on a life of their own during this choreographed routine. There are hints of machine gun fire, of artillery blasting way off and lamps lighting up strategic locations. Neither lights nor sound make much sense on their own, but together they create a kind of music which is both beautiful and ugly in equal measure.

What makes the Tesla Coil stand out is its ability to make light and sound together, projecting violent purple lightning bolts into the ether as it creates a crackling buzz like a robot struggling to communicate. Its arms reach out to the alien forms around the room.

When they all come together to create music as one, the mixture of light and sound is something that wouldn’t be out of place in a dance club, as strange rhythms and images are made, disorienting us and pounding our skulls.

There’s no narrative to speak of, but there’s certainly a progression. We move from blips of light and noises which sound like metal struck in the darkness to a cacophony of electricity which has as visceral and immediate an impact as it’s possible to feel in a theatre. Then, at the end of it all, as everyone else has bowed out, the Tesla Coil has the final word, completely spent and waiting for the next spontaneous symphony.

Ecstatic Arc is at Summerhall until 25 August. For more information and tickets visit the Edinburgh Fringe website.