All across South Korea, at exactly 08:40 local time (23:40 GMT Wednesday) on Thursday, more than half a million students take the exam for which they have been preparing their entire lives.
The infamous Suneung, an abbreviation for College Scholastic Ability Test (CSAT) in Korean, is an eight-hour marathon of back-to-back exams, which not only dictates whether the students will go to university, but can affect their job prospects, income, where they will live and even future relationships.
"For us, Suneung is a very important gateway to the future. In Korea, going to university is very important. That's why we spend 12 years preparing for this one day. I know people who've taken this exam up to five times."
Every year in November, Suneung brings the whole country to a standstill.
Silence descends across the capital Seoul as shops are shut, banks close, even the stock market opens late. Most construction work halts, planes are grounded and military training ceases.
Occasionally the stillness is broken by distant sirens - police motorbikes racing to deliver students running late to their exam.
Many nervous parents spend the day at their local Buddhist temple or Christian church, clutching photos of their children - prayers and prostrating are sometimes timed to match the exam schedule.
Source: BBC Online