Alternative titles : "Formidable Rivals", "Formidable Opponents", "Powerful Rivals"
Young-Jin, a 27-old-lady with natural born pride and desire to succeed and be recognized is not backed up at all by her poor family; rather she needs to take care of all of messes and fusses that her grandfather, father, and younger brother committed. Having nothing to trust except for her own body and soul, she exerts herself to finally be appointed as a body gourd of the Blue House of Korea. At the Blue House, Young-Jin meets Kwanpil, a smart, excellent, cynical and charismatic colleague, who by instinct recognize each other as formidable rivals. They bump into each other at every course of training, extremely competing to beat the other, and what a mischievous fate! They end up being partner to protect Suho, the only son of Mr. President. Suho is an unstoppable rascal with high intelligence and violent nature. Suho is the key person who discloses the past of Kwanpil and realizes the true virtue of family and love. By describing two vivid characters Youn-Jin and Kwanpil, [Formidable Rivals] shows the life of body guards who by nature cannot be spotlighted. This is the story of the others, non-heros, who support protagonists. They also have their own way of life, own value of family and love.
Cha Yeong-jin is a 27-year-old lady with natural born pride and desire to succeed and be recognized. But she is not backed up at all by her poor family; rather she needs to take care of all of messes and fusses that her grandfather, father, and younger brother committed. Having nothing to trust except for her own body and soul, she exerts herself to finally be appointed as a body guard of the Blue House of Korea. She’s the first female bodyguard who goes in cold and has plenty of stamina.
Kang Soo-ho, the only son of Mr. President, is an unstoppable rascal with high intelligence and violent nature. He is very nervous, picky, arrogant and self-centered. But Suho is the key person who discloses the past of Gwanpil and realizes the true virtue of family and love.
Yoo Kwan-pil is an excellent, cynical and charismatic colleague of Yeongjin. He is a different class from others. He is smart and tough. By instinct Gwanpil and Yeongjin recognize each other as formidable rivals. They bump into each other at every course of training, extremely competing to beat the other. They end up being partners to protect Suho, the only son of Mr. President.
More Than One's Expectations!
Kang Suho, the President’s son, always gets into trouble causing the President (Kang Min-kuk) to be embarrassed. He even escapes from the Blue House and joins an illegal gambling on the President’s birthday. The frustrated First Lady (Shin Ok-hee) asks the presidential guards to create a special team to keep an eye on Suho. Cha Youngjin and Yu Gwanpil, the two rival trainees for presidential guards get into a fight every time they see each other. After creating a ruckus on the training grounds, the two face a risk of being disqualified and not being commissioned if they don’t cooperate. Chief Pyo, who has observed Youngjin and Gwanpil, decides to let them watch over Suho.
Hot vs Cold
On her first day of duty, Youngjin is late for work and makes a big mistake to Suho and the President. Furthermore, she faints in front of the President. Suho tries to escape from the hospital where he has been treated but Gwanpil brings him back. The presidential guards are surprised to see the President warmly welcome Gwanpil in the hospital. Meanwhile, Suho suggests that Youngjin and Gwanpil should quit the job unless they can stand Suho for a week.
Faster and Meaner
Suho keeps on irritating Youngjin to make her give up the job of protecting himself. To bother her, Suho wakes up Youngjin every night. But Youngjin is not the type to give up anything and patiently endures all of Suho’s childish pranks. Meanwhile, Suho is chased by gang members involved in illegal boxing and Youngjin and Gwanpil struggle to protect Suho. Suddenly, Suho falls unconscious.
Owing to the trouble at the night club, Suho is ordered by the court to do community service for two weeks. Gwanpil and Youngjin are reprimanded and get under probation because of Suho. However, Suho asks them to continue working for him. Now, Suho has to help the elderly out by redoing wallpaper and Gwanpil and Youngjin are responsible for escorting Suho and preventing him from causing any other trouble. Youngjin witnesses thugs beat up her family threatening them to pay the debt of $3,000 plus interest.
Mind Your Own Business
Youngjin is upset that Gwanpil and Suho find out what her family is really like. She feels her pride wounded because of her clueless grandfather, dancing dad, and jobless brother. Unexpectedly, a girl in elementary school comes to see Youngjin, introducing herself as Yu Gwanpil's daughter. Gwanpil and Youngjin promise each other to keep quiet about Youngjin’s family and Gwanpil’s little daughter. Suho comes to guess Gwanpil likes Youngjin and declares that he’ll steal Youngjin from Gwanpil.
To Trust or Not to Trust
Gwanpil misunderstands Youngjin that she didn’t keep a secret and spread the rumor about his daughter Lily. The fact that Gwanpil has a daughter out of wedlock and that he kept that a secret become a problem. Consequently, the personnel committee opens a hearing to decide whether Gwanpil's employment is valid and Youngjin is asked to testify against him at the hearing. Doing community service with Youngjin and Gwanpil, Suho slowly falls for Youngjin.
The Definition of a Meter
Suho asks Youngjin to come out with him late at night and Youngjin gets into trouble while escorting Suho. Gwanpil on duty hears something bad happened to his daughter Lily. Suho begins to develop feeling for Youngjin. Gwanpil advises Youngjin to keep a distance of a meter from Suho.
Father, My Father
Suho wants Youngjin’s father Cha Gwang-su to teach him how to dance. Feeling embarrassed that his father is a third-rate dancer, Youngjin struggles to stop Suho. She says if Suho insists on learning to dance, she’ll quit the job. However, Mr. President tells Youngjin that he’d like to ask her father to take care of Suho. Meanwhile, death threats are delivered to Suho. Youngjin and Gwanpil attend a party to protect Suho from possible attack.
Memory of Vocalise No. 14
Suho disappears from the party, making his bodyguards nervous. Seeing the scene that Suho abruptly kisses Yeongjin, Gwanpil hits upon a memory of Suho and Eunyeong in the past and gets disturbed. Yeongjin tries to focus on her job as if nothing has happened while Suho gradually changes in a positive way. Concerned Gwanpil asks Suho not to force his feelings on her and finds out Suho has lost his memory and doesn’t remember anything about how the accident occurred 8 years ago. Realizing Suho’s feelings for Yeongjin is genuine, Gwanpil also warns Yeongjin just to concentrate on work.
Suho confesses to Yeongjin that his nightmare starts to end thanks to her. Suryeon feels uneasy for Gwanpil working for the Blue House near Suho. So she asks Yeongjin to protect Suho from Gwanpil. Bored of staying home alone, Lily hangs out at Mr.Cha’s dance studio where Suho is learning how to dance. Seeing the violin case that Lily carries, Suho starts to remember the day of the accident. Meanwhile, reporter Ko Sujin stalks Suho to find out what has happened between Suho and Gwanpil.
After realizing Gwanpil has a daughter, Suho gets his memory back and remembers what happened 8 years ago. With recovering memory, Suho is overwhelmed by heartbreaking grief and feels frustrated to barge in Youngjin’s place late at night. Youngjin, who suspects that Gwanpil has something to do with Reporter Go, starts tailing him. Pressured by the past memory, Gwanpil submits his resignation to the Chief Presidential Guard in an attempt to undo a situation.
The Truth and Its Duality
After recovering his memory, Suho has a quarrel with Suryeon who tries to keep the incident a secret. Accidently overhearing what they are saying, the First Lady comes to know the truth that Lily is the daughter of Suho. Now, the President’s family faces a new crisis. Suho meets Gwanpil and apologizes for all the things his sister did to Gwanpil and Eunyeong. Gwanpil asks Suho not to try to change anything saying Lily is now his daughter. Yeongjin calls on reporter Ko Sujin, who has been stalking Suho, to keep her mouth shut. Youngjin asks Sujin not to bother Suho and Gwanpil any longer. Unexpectedly, a tabloid publishes an article saying “The President's Son Has Secret Daughter.”
People and More People
After the article about Lily got released, Yeongjin is cornered to get fired unjustly. That’s because her supervisor Nam Dowu lies that Yeongjin is the source for the story. Hearing about the news, Suho and Gwanpil try to seek the truth and prove that Yeongjin is innocent. During the process, Gwanpil sees Suho’s sincerity toward Yeongjin and Lily. Despite the efforts of Suho and Gwanpil, Yeongjin is forced to resign and finally submits her resignation letter. She asks Suho and Gwanpil to host a farewell party.
What a Difference a Day Makes
Yeongjin, Suho, Gwanpil and Lily go out to the beach. They have a great time there and clear out the misconceptions on each other. Gwanpil and Lily are invited to the dinner with president’s family, and Gwanpil gets confused seeing Lily happy with the family. Feeling guilty to keep Lily with him, Gwanpil gets drunk and comes to see Yeongjin late at night.
Gwanpil agrees to take Lily to the president’s residence every weekend, but suffers from the empty space of Lily. Yeongjin goes to see Gwanpil to comfort him, and gets confused with her feelings for him. Suho does his best to open Lily’s mind and makes up his mind to enter to the National Dance Contest. Yeongjin runs after a stranger, who has been following Suho, and gets into a danger…
Rules of Happiness
After Yeongjin got attacked by the suspicious man, the security office is putting all their efforts to find out who the culpit is. Suho, practicing hard for the dance contest, sees the love and true hearts of the people around him. Appreciating the supports, Suho starts to have warm feelings about the world. On the competition day, the battle between Nam Dowu, targeting Suho, and the security office begins…