I also watched a fair share of Korean movies, some the title I can't recall. Will try to remember and add on to the recommended list.
Korean:
Forgotten
Plot Synopsis (taken from Asian Wiki):
Jin-Seok (Kang Ha-Neul) moves into a new home with his older brother Yoo-Seok (Kim Moo-Yul), mother (Na Young-Hee) and father (Moon Sung-Geun). Jin-Seok suffers from hypersensitivity, but with medication he is able to live normally. One rainy evening, Jin-Seok sees his older brother being thrown into a van by a group of men. After 19 days of silence, Yoo-Seok returns home, but he doesn't remember anything from his disappearance. Jin-Seok though notices enough changes in his older brother's personality and behavior that he begins to suspect that the person who has returned is not Yoo-Seok. Meanwhile, Jin-Seok keeps hearing sounds from a locked room temporarily storing the previous home owner's belongings.
POV: Brilliant. I love the movie *cough* Ha Neul *cough*
There's definitely a plot twist and you probably won't see it coming. Everything seemed to perfect and normal that you barely suspect anything. As usual excellent acting from Ha Neul and Moo Yul's part. So far Ha Neul's movies/ dramas have not disappointed me and yes, he's one of my favourite actor. Currently serving military, can't wait he's back into the acting industry. Fighting, Ha Neul!!!
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Vanishing: A Boy Who Returned
Plot Synopsis (from Wikipedia):
A 13-year-old boy named Sung-min and his two friends went missing after their venture into a cave in a forest, along with Su-rin. Later, a mysterious man in his 30s shows up and tells Su-rin that he is her friend Sung-min.POV: I enjoyed this film. I refused to sleep even though it was almost 1.30am as I needed to know what happened and what's the ending. It was
that good, and that engaging. At one point in the film, you'll be lost in the children's world where they were stuck in time. And then of course, tragedy strikes. Bad things happen to innocent children as well.
However, you'll also find a little bit of 'pedophile' element in the movie. Their love is pure though, so long you don't look at it in a strange manner, it's all innocent and beautiful. I chose to see it from the latter's angle
Also, I fell in love with Gang Dong Won after watching this movie. Since then, I always look forward to his movies on tvN
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A Werewolf Boy
Plot Synopsis (from Wikipedia):
Kim Sun-yi, an elderly woman in her sixties living in the US, receives a phone call about the sale of her old family home back in South Korea. Returning to her homeland, she's met by granddaughter Eun-joo, and they drive to the house in the country and stay the night. Sun-yi recalls how 47 years ago when she was a 17 year old girl in 1965, she moved from Seoul along with her widowed mother and her sister Sun-ja to a remote valley to undergo a period of convalescence after suffering problems with her lungs. The Kims lived in genteel poverty at the mercy of their arrogant and foppish landlord, Ji-tae, son of the business partner of Sun-yi's late father. Because of her delicate health, the beautiful yet introverted Sun-yi lives an isolated life in the country home, without any friends her age.
One night, Sun-yi glimpses a shadow in the outhouse; the next day, she discovers a feral boy of about 19 crouching in their yard. The boy's body temperature is 46 degrees Celsius, his blood type unidentifiable, and he can neither read nor speak. Even though he behaves like a wild beast, Sun-yi's kindhearted mother adopts him and names him Chul-soo, assuming he's one of more than 60,000 children orphaned in the Korean War.
At first Sun-yi considers him a nuisance, but eventually has fun taming him according to a dog-training manual. She teaches him how to wait patiently before a meal, how to wear clothes, how to speak, how to write and other human behavior so that he could one day live like a normal man. Chul-soo demonstrates unswerving loyalty and superhuman brawn, thus inspiring the envy of Ji-tae, who lusts after Sun-yi.
As Sun-yi attempts to "civilize" the beast, the two eventually become very close.
Pez: Watch it to know what happens later on and the ending!
POV: Yet another fantasy genre that captured my heart. How can I not watch this film that features 2 of my favourite actor? This is an infamous movie that many people would know even if they don't watch Korean films. Some would have probably seen it too.
By all means, as long as you have a pair of eyes, a beating heart and hand, please, watch this. One of the most moving, beautiful and touching movie. If you wanna talk about the ending, use spoiler.
Spoiler:-
» Click to show Spoiler - click again to hide... «
I'm so frustrated by the ending. Yes, it makes me angry, even now whenever I think about it

seriously? She should have spent her last remaining days with him. Any idea how much he suffered and how long he waited? Damn you auntie!
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A Violent Prosecutor
Plot Synopsis (from Wikipedia):
Byun Jae-Wook (Hwang Jung-min) is a short-tempered prosecutor who only pursues the truth. He is notorious for his rough and tough investigations. A suspect who is a small-time criminal, under the interrogation of Byun Jae-Wook, is then found dead. All the evidence indicate Byun Jae-Wook as the criminal. Byun Jae-Wook is prosecuted and gets 15 years in prison.
At first he is ill-treated by the prisoners. He helps some guards to avoid court room fees and in other legal matters. This gains him a special position in prison. He helps out both the officers and prisoners who are in jail through his legal knowledge and experiences. This makes prisoners loyal to him and he treats them well whenever he receives gifts from the guards. People in jail call him “Sir Young Gam” which means clever person.
Five years later, Byun Jae-Wook meets young fraudster Chi-Won (Gang Dong-won), in prison. Chi-Won knows details about Byun Jae-Wook’s case. Byun Jae-Wook trains Chi-Won to carry out his plan outside of prison. Using his knowledge as a former prosecutor, he gets Chi-Won free. Byun Jae-Wook prepares a counterattack on those who framed him. Although Chi-Won takes the chance to get away from Byun Jae-Wook, the other prisoners whom Byun Jae-Wook has helped get an early release don't let Chi-Won get away. Byun Jae-Wook and Chi-Won get together and start planning against Jong-Gil (Lee Sung-min) who was the Asst. Prosecutor General during Byun Jae-Wook's trial period and the person who had convinced Byun Jae-Wook to defend himself in a self-defense manner which resulted in his jail time. It is revealed that Jong-Gil, who is running in an upcoming election now, then was working with a builder to encroach an ecologically significant land. The rest of the film follows how Byun Jae-Wook through Chi-Won piles up evidences against Jong-Gil and gains his freedom.POV: Omg Gang Dong Won again

nay, I'm not biased, definitely not hehe. No, not biased
As read from the plot, it's a crime-thriller-prosecutor-drama sort of stuffs. Comes in with a bit of black humour, warmth and suspense. You can call it a typical movie, but it always give me that satisfaction due to the feel-good factor from this kind of show. Yes, definitely recommended
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I have space for only 1 more movie so I'll go into something darker:
The Crucible/ Silenced
Plot Synopsis (from Wikipedia):
Kang In-ho is the newly appointed art teacher at Benevolence Academy, a school for hearing-impaired children in the fictional city of Mujin, North Jeolla Province. He has a dark past - his wife committed suicide a year ago, and his sick daughter is under the care of his mother. He is excited to teach his new students, yet the children are aloof and distant, trying to avoid running into him as much as possible. In-ho does not give up trying to show the kids that he cares. When the children finally open up, In-ho faces the shocking and ugly truth about the school and what the students have been enduring in secret: the children are being physically and sexually abused by their teachers. When he decides to fight for the children’s rights and expose the crimes being committed at the school, In-ho teams up with human rights activist Seo Yoo-jin, but he and Yoo-jin soon realize the school’s principal and teachers, and even the police, prosecutors and churches in the community are actually trying to cover up the truth. In addition to using "privileges of former post" (Jeon-gwan ye-u) the accused do not hesitate to lie and bribe their way to get very light sentences.POV: It's a really disturbing film so I suggest skipping it if you can't take this. It's unbelievable that these a**h**** managed to get away. What is justice?
This film is based on a true story, thus making one feel even more disturbed watching it.