Although there are some action scenes and the story is based on human cloning, the film is philosophical.
It has a deep core and asks deep questions.. Why do we fear death? Why we want to live forever?
Is "how long we live" more important than "how we live"?
Are we living well?
Is there a purpose for our life?
The moment our death approaches, will we say that we regret or that we are proud of how we lived?
What would the world look like if humans could choose to live forever?
The film indirectly answers all these questions. And in the end Ki Heon answers the most important question.... Do you know now how the world gonna be if humans could find a way to immortality? And he answers, "Yes, I know."
Ki heon represents a normal human who fears death and wishes to live longer and Seobok is immortality sought by everyone.
If you are expecting an action movie, the movie will be disappointing. It is a philosophical movie about human nature, death and life. And how humans might destroy each other if they could control who lives and who dies.