Shin finds himself out of his comfort zone as he accepts a dangerous assignment. When things go horribly wrong, It changes his destiny, and the fates of everyone around him. Can the miracles of modern science, and the mysteries of an ancient past, bring him back from the brink of death?

Shin learns the history of his past existence, as he continues to heal from his life threatening injuries. Kim Lee continues to share the information in the journal written 400 years ago, and realizes the many similarities between Shin and his counterpart from the past. 

As Min Ho and Dr. Jin prepare to perform a life altering surgery to restore Shin to his former self. Shin relives disturbing memories from his past life.  

Kim Lee has doubts about the content written in the old journal. Shin realizes that although the storyline has taken an unusual twist, he can't help but be drawn in, as he learns the details of how a common man became an indomitable warrior. 

Kim Lee and Shin, continue to look back into the past. Learning the details of his donors history. And the strong bond of friendship that starts to develop between the armory captain and the warrior who becomes known, as the Iron Mantis

As Kim Lee finishes up reading the journal. Shin begins having dreams, filling in some of the historical gaps left out of the story. Shin's surgery is a success. His recovery defies all expectations. But Shin begins to have trouble discerning dreams from reality. 

Shin's recovery continues to amaze Dr. Jin and his staff, as his progress continues way ahead of schedule. Shin's dreams become more confusing. He tries to determine if they are real, or just a reaction to his physical or mental condition. But he has to come to terms with the events that led to his death in a previous life. 

Shin's recovery continues to defy all expectations. He is reintroduced to friends and the outside world. Kim Lee and Shin learn their whole lives were planned by a secret society. Shin comes to realize, the life he once took for granted, is full of blessings.

Shin settles in with Kim Lee and his family. Shin's new found appreciation for life, gets him to re-think his past perception of where he fit in. Cindy tries to play matchmaker between Shin and one of her friends. Shin's cover might be blown, after being forced to defend himself from a couple of local gang members.

After the incident at the souvenir shop, an unscheduled briefing is called to do determine if Shin's actions would draw unnecessary attention to the investigation. The computers that monitor Shin's bodily functions crash, causing Dr. Jin and Min Ho to become concerned for his recovery. Cindy once again tries to play matchmaker with Shin. Shin uses the opportunity to get to know Min Ho better.

Shin gets some bad vibes from Dr.Hyo. Soo Young gets a hot lead on the case. Shin's new found abilities magnify his advanced computer skills. As the team realizes Shin's power, It starts to become obvious to everyone, the need to evaluate the situation.

As new developments in the case come to light, The unusual diversity of their group start to form a team. Soo Young lets her guard down and reveals to everyone her uncomfortable secrets. Shin begins to understand the presidents observation that Cindy will bring balance to the team.

Shin begins to understand his ability to connect to, and directly interact with anything connected to the internet. Cindy is given an important roll on the team. She gets her first glimpse of what Kim Lee is really like on the job. Shin's digital attack on the North Koreans servers is a direct hit, setting the international intelligence community ablaze. Shin and Min Ho make arrangements to visit the orphanage where Shin was raised. 

Shin and Min Ho visit the orphanage he was raised in. It confirms to Min Ho, that Shin is the man she presumed him to be. But the realization of his extreme code of honor, causes her concern. Shin gets better at manipulating technology, and adapts to using it easily. Shin discovers an army of assassins are preparing to make their way from Japan. Soo Young and Kim Lee assemble tactical teams, to try to intercept them, before they infiltrate the general population. Cindy tries to come to terms with the recognition that Kim Lee's job, is full of dangerous assignments. 

As the team formulates a plan to deal with the assassins coming from Japan. Shin begins to observe the development of a strong bond between each of its members. Cindy comes to realize why Kim Lee has been very guarded about letting her know too much about his duties at work. Doctor Hyo begins to blend in as part of the team reluctantly. And it turns out, Kim Lee and Shin's suspicions about Soo Young's abilities were well-founded. 

The team regroups, to try to find out what went wrong with the prisoner transport. Kim Lee finally get permission to use the military grade drones, but things don't go according to his plan. Dr. Hyo drops a reality bombshell on the team that causes them to rethink everything. Shin reveals to Dr. Jin about the changes in his sleep pattern. Soo Young puts Shin's extraordinary abilities to the test with surprising results. Soo Young expresses to Shin her feelings of guilt about the day he was shot. 

As the team regroups and attempts to recover the escaped assassins. Soo Young and Shin form a risky plan to trick the enemy into disclosing the information needed to regain control of the situation. Soo Young brings in an outsider to help facilitate this risky operation. Shin continues to make observations concerning the team's development.