Cart Macabre, Old Vic Tunnels, London

I have to admit to being vaguely nervous before seeing Cart Macabre. And, as it happened, all the rumours I'd heard – that the show featured absolute pitch blackness, white hospital- stretcher-type wheelbarrows that transport you to waiting wooden carts seating four people each and sailor songs about purgatory – all proved to be true. Yet there's more to the show, which is part theatre, part performance and took two years for the Living Structures collective to develop, than that.

After relinquishing coats and belongings (strangely it was actually warmer in the tunnels than over ground) and lining up in a row, each person is selected at random by boiler-suited sailors to be taken down to the carts. Trundling noisily off, forward, sideways and possibly even round in circles – it becomes slightly disorienting so it's hard to tell exactly – the carts stop-start as various scenes appear. There are porthole windows that look like petri dishes and fuzzy CCTV cameras showing carparks. When part of the cart is removed, we see a tarpaulin surrounded cinema screen in one instance or an upside-down room with a girl tucked up in bed in another.

If the whole thing sounds slightly bizarre that's because it is. Sometimes it's difficult to work out what each scene means (as one line from a memorable sailor medley went, "your monkey brain won't understand") but the thread of the sailors who appear or sing in the background throughout just about manage to keep the piece on track. The final section, where all the carts are hooked together to form a kind of carousel is the best. There's so much to see in every direction.

There really couldn't be more a fitting venue than the Old Vic Tunnels either, as trains rumbling overhead add to the effect. Most importantly, the show combines the story of a journey into the murky underworld of nothingness with care from the company's actors. At the end, there's a feeling of real human spirit as everyone emerges, blinking into the light to a reassuring hug from a sailor and a final rousing chorus.

To 22 December (www.livingstructures.co.uk; www.oldvictheatre.com)