A room filled with glowing fog; shadowy figures among glittering LEDs and warm ‘breathing’ columns of light. Welcome to the trip that is Light Show (until 28 April), the Hayward Gallery’s latest exhibition exploring how artists have used the medium of artificial light over the past five decades. With side effects of disorientation, slight panic and hallucinatory visions, this exhibition is an intoxicating sensory cocktail, plunging visitors into a world that is recognisable and unfathomable at the same time.

With sculptures and installations that visitors can step into, Light Show is a fitting title for something that is, in many ways, more spectacle than ‘exhibition’. This art is entertainment; children stared hypnotised at the winking lights of Jim Campbell’s ‘Exploded View (Commuters)’, 2011, above, while couples held on to each other in the fragmented darkness of Anthony McCall’s ‘You and I, Horizontal’.

However, this twinkling spectacle has a dark undercurrent. Light also creates shade, as Conrad Shawcross’s ‘Slow Arc Inside a Cube’ shows, trapping visitors in a cage of shadows.

Walking through ‘Chromosaturation’, a three-room installation swamped in coloured light by Carlos Cruz-Diez, I found my foot inches away from a man lying on his back in the middle of the floor. Stepping over him, I heard him say to a friend, ‘It’s red…but it’s too red to be red. Do you know what I mean?’

No, actually. No one knows what you mean. But he had a point. This exhibition forces us to question what we know about artificial light. We trust it; it illuminates our reality. Light Show destabilises this implicit trust.