I truly enjoyed this action movie. It has a really simple but efficient concept, focusing on a frightening cat-and-mouse chase between a serial-killer and a deaf woman. With very few characters and plot points, the film manages to keep the viewer on its toes during the dark pursuit.

The scenario relies a lot on people making not so smart decisions as well as a lot of police incompetence which might make your blood boils...There are a lot of successful jump scares and action sequences are really well-done. As one of the character is deaf, the surrounding noises and sounds carry a particular importance on the story. It amps the viewer's anxiety as the filmmaking manage to make the watcher understand how it is to be in the shoes of the victim.

The casting was really good, especially Wi Ha Joon who delivers a shockingly horrifying performance. I only saw him in two other roles playing overall good characters so the shift here truly astonished me. Jin Ki Joo acting as his main counterpart was also very solid in her role.

I would recommend this to people looking for a thriller that will brought you all the feels in a very short time. It is very dark and efficient in providing thrills with some good jump scares and action sequences. It might require some suspension of disbelief given the reaction of some characters that might seem completely stupid. But, honestly that did not bother me because I found the story gripping enough to not care about the script flaws. I just went on a scary ride and enjoyed it for what it was.