Set 3 years after the first season, members of the National Security Service (NSS) team, including Jung Yoo Gun (Jang Hyuk), Ji Soo Yeon (Lee Da Hae) and other agents attempt to pull the curtain on mysterious group IRIS.
Agent Yoo Gun is the leader of NSS TF-A team. While he goes up against Baek San (Kim Young Chul), Yoo Gun becomes involved in a case which changes his fate forever.
In this anthology film centered around the theme of "Eros," five separate stories are presented. The main characters from each segment are connected with each other in one way or another.
"His Concern"
A man is attracted to the woman sitting across from him on a train ride to Busan. He then gets off the train after her, even though it's not his stop. He is then able to get her phone number. A few days later the man plans to meet the woman for the second time.
"I'm Here"
Ahn Hye Rim awaits her husband, while hiding, to give him a surprise. Kang Hyeon Woo always worries about his wife being left alone. Hye Rim worries about Hyeon Woo because he will be left alone soon.
"33rd Man"
On the set of a movie, fresh new actress, Kim Mi Jin, and her charismatic senior actress, Park Hwa Ran, are having difficulties because of their stubborn and demanding director Bong Jan Woon. In the end, the senior actress Hwa Ran transforms Mi Jin into a sexy vixen to seduce the director.
"In My End is My Beginning"
Lee Jeong Ha learns that her husband Min Jae In has just died in a car accident while on a road trip. She then discovers that her husband was having an affair with her old high school friend Kang Na Ru. After the car accident, Na Ru comes to Jeong Ha and asks to live with her under the promise of her unconditional devotion.
"Believe in the Moment"
Three couples are all high school students and close friends. None of the couples have strong convictions about their relationship. They then decide to exchange partners for 24 hours.
The Empress is in her early 30s, but she is still not married. Since the 1st successor to the throne died, the royal family is in search for a new successor. Incidentally, they come to know of a young man who was, in fact, the prince's son of a woman who left the Palace in order to keep her pregnancy a secret. The young man's name was Lee Hoo, more commonly known to his friends as Kang Hoo.
Lee Hoo worked as a delivery boy at a Chinese restaurant and was known for his 7-minute maximum delivery time. Lee Hoo had been brought up as more of a punk than a prince so his habits and his way of conversing were very different from the people of royal blood. Although he had never dreamt of living in the Palace, he one day finds himself immersing himself in its grandeur and improving himself to prove that he indeed deserves to be called the Successor to the throne.
He soon finds out that not only will he be facing lessons to the path of royalty, and dilemmas of love and of stature, but he will also learn to compete for the position he had been, first and foremostly, called for.