SEOUL - South Korea went into "hush" mode Thursday, as nearly 650,000 students sat the annual college entrance exam that will play a large part in defining their adult lives in an ultra-competitive society.
Preparation for the crucial exam starts from primary school, and so does the relentless pressure which has been blamed for everything from early burnout to teenage depression and suicide.
A 17-year old boy was found dead Wednesday evening having apparently jumped from the window of his family's apartment. His parents told Yonhap news agency that he had become extremely stressed as the test neared.
Success in the exam means a secured place in one of South Korea's elite universities -- a key to future careers as well as marriage prospects.
With so much riding on the outcome, the day of the test -- held simultaneously in 1,257 centres nationwide -- sees the entire country switch to silent running.
The transportation ministry bans all airport landings and departures for a 40-minute period to coincide with the main language listening test.
The military also reschedules airforce drills and live-firing exercises, while traffic is barred within a 200-meter radius of the test centres.
Public offices and major businesses, as well as the stock markets, opened an hour later than usual Thursday to help keep the roads relatively clear and ensure the students arrived on time for the exam which began at 8:40am.
Anyone who did get stuck could dial the emergency number 112, and request help from police cars and motorbikes on standby to rush them to the centres.
At Seoul's Pungmoon Girls' High School, junior students huddled together in the -3C (26.6F) cold held good-luck banners and shouted encouragement as their seniors entered the exam room.
For the equally stressed parents, there was little left to do after a final hug at the school gates.
Many immediately made their way to nearby churches and temples in search of some divine intervention.
Major internet portals and social networks were flooded with good-luck messages, and "test-takers" and "jackpot for the test" were among the top-trending topics for Korean Twitter users on Thursday morning.
Some warned against taking the exam too seriously.
"Don't do anything stupid," wrote one user on the top Internet portal Naver. "Don't kill yourself just because you mess up the test. There are many people who succeed in life without going to college."
Genuine test of ability?
The approach of exam day tends to renew a perennial debate in South Korea about the country's obsession with education and the pros and cons of the college entrance system.
The bottom line for many is that the examination itself is fair. Everyone takes the same paper, which relies on the multiple choice system to prevent subjective marking.
But bitter disputes still occur.
A question in the Geography section of the 2013 exam -- worth three points out of a total 340 -- became the subject of a costly, year-long legal battle after the officially correct answer was challenged by some students and their parents.
Security is absolute, with the hundreds of exam setters sequestered for more than a month in a secret location, which they are only allowed to leave once the test has been taken.
They are kept in total isolation, denied phone contact with their families and with everything down to their food waste subject to rigorous examination.
According to the Education Ministry, South Korean parents spent 19 trillion won (S$20.5 million) on extra tuition for their children last year -- equivalent to about 1.5 per cent of the national GDP.