As a frequent insomniac, a show that promised “sublime” slumber was impossible to resist. Still, I entered the Barbican full of scepticism. Given how much trouble I have falling (and staying) asleep in the security of my own home, I didn’t hold out much hope for doing so on my first sleepover party since the age of 16, held in the subterranean Pit with 50 strangers.

But Lullaby, Duckie’s new, totally immersive theatre experience is designed to soothe and comfort from start to finish. On arrival at 10.30pm, you check yourself and your bags in and are then escorted by pyjama-clad stewards from changing rooms to toilets to your surprisingly comfortable and beautifully dressed (by Toast) bed. Once all audience members are tucked in to their singles, doubles or triple, the winding of music boxes signals the start of the performance.

It’s all gentle stuff – choral singing, light shows, a troupe of octopi with glittering tentacles, slightly surreal adult storytelling, counting sheep, balloon displays, a circular dance of pillow creatures mimicking the rotations of a cradle mobile. After a “pause”, rather than an interval, for toilet breaks and a last mug of cocoa, the second act gears up (or winds down) for a proper send-off.

The last thing I remember, some time after midnight, was a cello and an interplanetary lecture. Hours later, I woke at 7.30am – the first time I haven’t risen at least three times in the night in months – to find a few little surprises hatched centre-stage and eggs being served in the breakfast room.

Over the years, I’ve struggled, as all regular theatregoers have at some point, to stay alert through countless numbing productions, so it feels strange to acclaim a show for being soporific, but I must here – and that’s high praise indeed from me. It won’t be everyone’s cup of cultural cocoa, but, at just £42 with breakfast, beverages and earplugs included, it’s cheaper than a hotel – and far, far cheaper than the insomnia doctor I consulted last year.

As there was no chance to applaud at the end, let me now – an hour after returning to the office from my Barbican stay and feeling far more refreshed than usual – raise a pillow and a happy yawn to the Duckie team – creators and performers H Plewis, Harriet Plewis, Matthew Robins and Tim Spooner, director Mark Whitelaw, designer Laura Hopkins and all the stewards. I did indeed have a good night’s sleep and am very grateful.