As the haze darkened the Singapore skyline last Friday evening, thousands gathered on Hollywood Boulevard inside Universal Studios Singapore (USS).
Loud rock music blared from overhead speakers and there was a murmur of excitement. A man in a white lab coat and black goggles, carrying a Bible, stood up on a raised platform and pleaded with the crowd.
"It's not too late for you. Please get out," he warned, with distress in his voice. "[The] darkness will descend."
The crowd roared. The more harangued he looked, the louder the crowd became.
It was not a reenactment of classic horror movie trope; it was the opening act - or "Scaremony" as it is called - of Halloween Horror Nights, the annual scarefest at USS. Terrified, and satisfied, customers are the result of up to a year of planning, building and training that involves hundreds of locals.
"What we're really finding is that the local and the regional guests love to come and pay and get scared, and spend the night and do everything that you would think you wouldn't want to do," said Jason Horkin, vice president of attractions at Resorts World Sentosa.
In its fifth year, Halloween Horror Nights 5 has four haunted houses and three scare zones in the theme park, with a slew of nightmare staples such as zombies, malevolent spirits, and aliens.
Three of the haunted houses were designed after local Singaporean horror legends and myths, which included a collaboration with Singaporean writer Russell Lee, which led to the creation of True Singapore Ghost Stories: The MRT. Inside the house, visitors walked through a series of scenes from a local haunted train station.
Other haunted houses included a trip through a local housing complex quarantined due to a virus outbreak.
Horkin told CNBC: "The locals don't really get scared from the Western ghost. They like the more Asian stories, so this year, we have very Singapore stories as well as more Asian themes."
Preparation for the annual Halloween Horror Nights start up to a year ahead, starting from conceptualizing the idea to building the sets to training the 400 characters scattered throughout the theme park.
"Set construction begins some time in July where the groundwork is laid," said Andrea Teo, executive producer of Halloween Horror Nights 5 in an email interview. "Plans are mapped out on the ground to scale before set construction begins in earnest. There may still be several rounds of changes and fine tuning at this stage and even as each set goes up."
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"Our goal is to create the region's best Halloween event with original storylines and intricate movie-like sets that provide unique horror experiences," said Teo. "We have found that using local experiences and familiar context and putting a horror twist to it works well with our local guests and makes for a really unique and different experience for guests from around the region and internationally."
Audition for the 400 characters begin in May. Some of the roles are given to full-time performers at USS, who are selected through an internal audition. Candidates for the rest of the roles are found through two rounds of external auditions. Once the roles are finalized, the candidates go through a series of technical and acting training for six to eight sessions, to get into character. The entire production goes through at least three full rehearsals before it is open to the public.
For a seasoned event, USS's Halloween Horror Nights remains popular among Singapore locals as well as tourists. Horkin said attendance had increased three-foldd from the first year.
"As long as people have new things and new ways to be scared, they keep coming back," he said.
And some visitors at the park agreed. One Halloween Horror Nights veteran told CNBC, "It's my third time [here]. I'm really interested in the costume, make-up; it's really professionally done, all of the sets."
While another said, "I get really scared quite easily. So I always love being scared, and here is the best place to get scared."