‘The Nightmare Realm’ runs from 9 October to 1 November 2026.
The horror attraction will take over Avery Hill Mansion in Greenwich.
Two original experiences, ‘Avery Hill Asylum’ and ‘Sundown Manor’, will feature more than 70 actors.
The immersive horror attraction has been spooking Ireland since 2009.
Halloween in London is about to become considerably more frightening. ‘The Nightmare Realm’, an immersive horror attraction from Ireland, will make its capital debut from Friday, 9 October to Sunday, 1 November 2026.
The independent production will transform the grounds of the Victorian Avery Hill Mansion in Greenwich into a large-scale world of sinister characters, unsettling stories and theatrical scares. More than 70 actors will take part in The Nightmare Realm London event, leading visitors through two original horror experiences created specifically for the new location.
The first story, ‘Avery Hill Asylum’, unfolds inside a Victorian-style institution controlled by the mysterious Dr Thorne. Behind its doors, visitors will discover evidence of his strange experiments as they navigate dimly lit corridors and encounter the asylum’s unfortunate inhabitants.
‘Sundown Manor’ introduces a different kind of terror. The story follows an ancient Irish family that has arrived in London in search of new victims. Details remain deliberately limited, but the experience promises an original narrative that combines Irish folklore with the unsettling surroundings of the historic mansion.
Between the two attractions, visitors can regain their composure in Halloween Town. Described as a ‘living village’, the interactive space will feature roaming characters, secret rooms and food stalls. Although the atmosphere will be less intense than the main horror experiences, the attraction’s theatrical storytelling will continue throughout the village.
Timed entry slots will operate from the early evening until late at night. The entire visit should last approximately two hours, with around 75 minutes dedicated to the two principal horror stories.
‘The Nightmare Realm’ began in Tralee, County Kerry, in 2009 before expanding to Cork and Dublin. The attraction changes its narratives, characters and mazes each year, helping it build a loyal following across Ireland over more than 16 years.
Celebrity visitors have included Megan Fox, Emma Myers from ‘Wednesday’ and members of the Hamilton cast. Previous editions have also become known for secret rooms, costumed performers, live entertainment and interactive storylines that encourage visitors to explore beyond the main haunted mazes.
Tickets for The Nightmare Realm in London went on sale at 6pm on Monday, 3 August 2026.
Where: Avery Hill Mansion, Bexley Road, London SE9 2PQ.
When: 9 October to 1 November 2026
Contact: https://thenightmarerealm.com