Ha Mu Yeon's father killed himself after becoming a suspect in the case of the Iltan killer, also known as Gap Dong. After the statue of limitations is up on the case, the original ... See full summary »




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Series cast summary:
Yoon Sang-Hyun ...  Ha Moo-yeom 20 episodes, 2014
Min-Jung Kim ...  Maria Oh 20 episodes, 2014
Dong-il Sung ...  Yang Chul-gon 20 episodes, 2014
Joon Lee ...  Ryoo Tae-oh 20 episodes, 2014
Kim Ji-Won ...  Ma Ji-wool 20 episodes, 2014
Sung-jae Choi Sung-jae Choi ...  Detective 20 episodes, 2014
Soo-Hyun Choo Soo-Hyun Choo ...  Oh Young Ae 20 episodes, 2014
In-gi Jeong ...  Cha Do-Hyeok 20 episodes, 2014
Ji-Hwan Jo Ji-Hwan Jo ...  Lee Hyung-nyeon 20 episodes, 2014
Nam-kil Kang Nam-kil Kang ...  Han Sang-hoon 20 episodes, 2014
Yoon Kyun-Sang Yoon Kyun-Sang ...  Detective 20 episodes, 2014
Min Sung-wuk Min Sung-wuk ...  Nam Ki Ri 20 episodes, 2014
Gwang Jang ...  Monk Jin-jo 18 episodes, 2014
Won-joong Jung Won-joong Jung ...  Park Joon-goo 18 episodes, 2014
Jae-jin Baek Jae-jin Baek ...  Psychiatric recluse 15 episodes, 2014
Hee-woong Jang ...  Seo Ji-hoon 15 episodes, 2014
Geun Jung Geun Jung ...  Park Ho-suk 15 episodes, 2014
Hee-soo Jang Hee-soo Jang ...  Kim Young-mi 14 episodes, 2014
Joo-hee Seo Joo-hee Seo ...  Ji Hwa Ja 14 episodes, 2014
Seung-yeon Jo Seung-yeon Jo ...  Kwon Oh-shin 11 episodes, 2014
Yae-min Jung Yae-min Jung ...  Ha Moo-yeom (young) 10 episodes, 2014
Min-Sang Kim Min-Sang Kim ...  Choi Tae-shik 9 episodes, 2014
Hyun Woo ...  Cha Do-Hyeok (young) 9 episodes, 2014


Ha Mu Yeon's father killed himself after becoming a suspect in the case of the Iltan killer, also known as Gap Dong. After the statue of limitations is up on the case, the original detective returns to continue his investigation. However, Moo-Yeom is now a detective and works to capture Gap Dong as well, refusing to believe that Gap Dong is dead. New evidence for Gap Dong appears in front of Moo-Yeom and he sets out to catch him once and for all. Written by Rebecka Ferian

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User Reviews

Gap : a hole between two objects & Dong : A resonant sound
13 March 2019 | by ankithbk-00980See all my reviews

And you will exactly feel what the title says....which no one yet understands...through out this psychodrama...Its a long resonanting sound that goes thorough 2 decades and no one can hear it...hence cant catch it!!!

The name is so apt after watching this fabuluosly crafted series....It gives you a hinge to hold on to everytime you even thing that you are loosing interest. The characters are perfectly placed with the right kind of development. The story might be inspired but relatively it gives a new direction to what actually have had happened...After watching a 100+ korean movies/dramas... i do say that it is one of the best.....although i stay true to my word " I saw the Devil".. will stand out forever!!!

There are flaws in the story line... but that dont matter when you have crafted something so beautiful and intellectually creative for everyone to indulgue with.

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Official Sites:

Official site [South Korea]


South Korea



Release Date:

11 April 2014 (South Korea) See more »

Also Known As:

Gap Dong See more »

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