The *true* killer from Gyeonggi.
No, not a character in the film - the actual Gyeonggi killer from the 80s.
There is a composite of his face. In fact, there was more information about him than the movie could pass onto the audience. There even was - and still is - a hauntingly good suspect... but, life not being a film, not much could have been done without evidence.
The killer - a composite from the 80s. In 1988, he was assumed to be about 160 - 170 cm tall and in mid to late 20s.
http://imageshack.us/a/img62/5006/mmmars.jpg
The killer, aged.
http://imageshack.us/a/img189/1806/mmkilleraged.jpg
The killer, in 3D, and age-progressed to his possible (and very unlikely) current appearance.
http://imageshack.us/a/img688/658/mmkiller.jpg
The real equivalent of the footprints that Park examined.
http://imageshack.us/a/img829/8594/mmprints.jpg
The real cops.
http://imageshack.us/a/img10/4741/mmprecinct.jpg
The road where Park stops in the end. The culvert is visible on the right.
http://imageshack.us/a/img35/2971/mmroad.jpg
The culvert...
http://imageshack.us/a/img811/7596/mmculvert.jpg