At dusk, like clockwork, streetwalkers in skimpy outfits emerge from alleyways. They flirt with men, both foreign and local, while being watched by minders on the alert for the police.
Off-corner massage parlours and hotels with hourly rates do a roaring trade. Nearby, peddlers sell sex drugs with names such as Super Magic and Tiger's Prestigious Life, while others deal in contraband cigarettes.
This is Geylang, Singapore's notorious red-light district and another foreign worker hot spot now in the spotlight after Police Commissioner Ng Joo Hee said last week that the area was a bigger concern than Little India, where last December's riot took place.
"If Singaporeans are irked by the littering, the noise and the jaywalking in Little India, they'll certainly and quickly sense that there exists a hint of lawlessness in Geylang," he told the Committee of Inquiry into the riot.
It is an area where disproportionately more crime and public order offences take place. Last year, Special Operations Command forces were deployed to Geylang on 41 occasions, compared with 16 in Little India.
Last Friday afternoon, auxiliary policemen were seen taking away illegal cigarettes which had been stowed in trash cans in an alley next to a Buddhist temple.
Crowds of hooligans, Mr Ng said, are not afraid of standing in the way of police work. He recalled how an officer was once beaten up when he tried to detain an illegal gambling stall operator.
Residents say some shops in Geylang are just fronts for criminal activities. Gambling dens, for instance, are set up in small rooms behind the main shop area, or up on the second floor.
Many businesses and residents The Sunday Times spoke to declined to give their full names or to be photographed, worried they might "offend someone".
Yet Geylang is also home to many migrant workers who reside in sometimes overcrowded shophouses offering cheap rent.
Electrician Chai Zhi Yuan, 41, from Jiangsu, China, admits it could get "chaotic" at night and on weekends.
"I don't go out much as it can get very messy. Instead, my friends would come to my place for drinks," he said.
Bangladeshi construction worker Tarikul Islam, 20, also prefers to stay in at night "because there is a lot of trouble outside". Added compatriot Sakil Alam, 25: "Every week, I see fighting here, because of drinking. Maybe sometimes because of the girls."
And then there is the risk of being caught in the wrong place at the wrong time.
"When I go out to buy food at night, the police often stop me and ask for my permit," said Mr Tarikul. "Maybe I am somewhere, not doing anything bad or causing trouble, but because they see me there, they think I'm also trouble."
Although MPs, grassroots activists and most residents are calling for Geylang to be cleaned up, the businesses - from coffee shops to KTV lounges and liquor shops - have a different perspective.
One provision shop owner said: "I really think no shop in Geylang will tell you, I want all this crime to stop. If they say that, they are lying. All these activities attract people, attract money."
Mr Teh Hock Koon, 50, who runs a bak kut teh stall in a coffee shop at the end of a row of bro-thels, told The Sunday Times: "The more 'complicated' an area is, the better it is to do business."
Since moving there a year ago, his takings have gone up by as much as 40 per cent.
Added a liquor wholesaler along Geylang Road: "Yes, police patrols will be good to bolster security, but it won't do us any good if the vice is completely stamped out either."
Already, five fast response squad cars are routinely deployed in Geylang every weekend - compared to three in Little India and one in most other estates. Two dozen uniformed officers conduct foot patrols, while plain-clothes police conduct checks on clubs and massage joints.
Mr Ng admitted that more could be done to enhance police presence in Geylang, and hopes to deploy 150 more officers there.
Retiree G. Goh, 62, who has lived in Geylang for over 50 years, said: "In the last decade, there were more foreigners coming. But they are not why there is crime now. There has always been crime in Geylang and the kings are your local fellows.
"The police who walk down the street will stop these foreigners, but they are all ikan bilis (small fish). The big fish, the whales, are all behind the scenes."