In a towering modern office building in central Jakarta, some of the employees are ready to call in a shaman. They say they have seen disturbing shadows and heard the sound of a woman sobbing in the deserted staff toilets.
"It has had an effect on the people, who are really scared," says one, who blames spirits and feels it is time to act. "If people are not happy working there because of the boss or the other people that's normal, but if it's because of something else . . . it's a simple step [to call an exorcist]."
Businesses around the world spend time and money making sure employees are happy in the workplace. For many, that means open areas with beanbags, free snacks or organising their dry cleaning. In Indonesia, it also means keeping the jinns at bay.
The world's largest Muslim-majority country, Indonesia is a nation where traditional belief systems, including animism and shamanism, have been fused with mainstream religions. Attempts by parliament to outlaw black magic have met with opposition from some who see the supernatural as a crucial part of Indonesian culture.
These beliefs also permeate the workplace. From cosmopolitan Jakarta to pious rural communities, most Indonesians have a story of a haunted office or a co-worker plagued by spirits that are affecting morale and productivity.
An industry has developed around the men who profess to ward off evil in workplaces, from small, locally owned businesses to household-name multinational corporations with many expatriate workers. Numerous office managers in Jakarta have a shaman in their phone book. And Abu Aqila, who has been charging for exorcisms at factories and offices for some 15 years, says his business is growing every day.
The 44-year-old has trained more than 100 people in his trade. They operate in and around Jakarta, billing businesses between Rp7m ($480) and Rp15m a visit. A small team of four or five turn up at office buildings in a smart uniform of black trousers and blue shirt emblazoned with Mr Aqila's company's name: "Bengkel Rohani", or "spiritual workshop".
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The process can last up to five hours. Mr Aqila starts by helping to pacify workers, before looking for supposed signs that evil spirits are haunting the building. These include cracked walls and broken lamps, as well as suspiciously strong odours. He then explains the cause of the "apparitions" to the workforce, before reciting verses from the Koran to drive away the spirits.
"Jinns like stuffy places — the engine room, dirty places, dark humid places that are empty," he says, speaking in his spanking new mansion, kitted out with slate flooring and a flatscreen television. "Or crowded places where there is a high stress level, where people are working under pressure."
Business is booming for the likes of Mr Aqila, who is called to at least one workplace every week.
With office workers approaching shamans of all faiths, the industry is also an unexpected reflection of religious tolerance in Indonesia, where some 87 per cent of the 250m population is Muslim but small Hindu and Christian communities coexist largely without conflict.
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One employee at a factory in Jakarta says her Christian boss invites a Balinese woman to perform Hindu rituals if there are signs of paranormal activity: "My boss has tried an ustad [Islamic shaman] before but in the end he is more comfortable using Hindu rituals."
Although dealing with evil spirits may be routine for executives in Indonesia, there are signs that younger, urban workers are rejecting belief in the supernatural. "The younger generation of people is busy with technology — the way they think is different," says one 51-year-old worker who has seen apparitions in his office. "In the big cities like Jakarta, Surabaya, Medan, I think, in 50 years this will all be finished."
But for now, business continues to grow as ever more offices pop up around Jakarta, providing custom for the shamans.