IT was through this gate that Tuong Van Nguyen's journey to hell began.
And as he sits on death row awaiting execution on Friday, Nguyen has no doubt reflected on the night the "beep" of the metal detector signalled the collapse of his world.
It was just on three years ago when the 22-year-old Melbourne salesman approached Gate C22 at Singapore's Changi Airport with much trepidation.
He was carrying two bags of high-grade heroin -- one strapped to his body and the other stuffed into a backpack -- and was rushing to catch the flight to Melbourne.
He was in transit from Cambodia, where he'd collected almost 400g of the white powder to smuggle into Australia for a Sydney syndicate.
Nguyen would later tell Singaporean police he had become a drug mule to pay off his twin brother's debts.
Airport security officers in Cambodia had failed to detect the two plastic packets of heroin he'd taped to his body.
Once on the Silkair flight MI622, Nguyen started to have breathing problems, so he went to the toilet and removed the packet taped to his stomach, then stuffed it in his hand luggage. He kept the other taped to his lower back.
After arriving in Singapore, Nguyen had to connect with Qantas QF 10 for his flight home.
But he fell asleep in the Business Lounge, and when he awoke realised he had only 10 minutes to make the plane.
In his police statement, Nguyen said his anxiety levels were further raised by fears that his movements were being monitored by the drug syndicate.
"At the metal detector, I placed my backpack and my business bag on to the X-ray machine," he stated.
"Then I walked through the metal detector and as I was crossing it beeped.
"At that point I knew I was going to be caught.
"A policewoman told me to stand to one side so as not to obstruct traffic.
"She then used a metal detector wand to search me by going up and down my body. The wand did not beep.
"She then touched my back and when she reached my lower back, she must have discovered the packet of heroin strapped there."
Nguyen, who has no criminal record, was immediately taken to a room where he was ordered to place his hands against the wall.
"I told him, 'No need, I will get it for you'," he stated. "I lifted up my shirt and pulled out the strapped packet on my lower back and gave it to the officer.
"He asked me what that was and I replied to him, 'It's heroin, sir'.
"I also told him that there was more and went and retrieved the pack of heroin which I had hidden inside my backpack."
At this stage, Nguyen became distressed and began to cry, at the same time hitting his head against the wall. He then sat on the floor, holding his head in his hands.
Shortly before midnight, December 12, he was taken to Singapore's Central Narcotic's Bureau and later charged on serious drug offences, with an automatic penalty of death by hanging.
It had been his first overseas trip.
Just before midnight last night all was quiet at Gate C22. About 5km away, the lights were also out at Changi Prison.
Nguyen's execution date falls on the third anniversary of the day he flew out of Australia.