Mi Yeong, Hye Yeong, Ra Yeong, and Joon Yeong are the kids of Yeong Sil and Han Soo. They seem like the average Seoul family, with the typical Seoul problems, but that all changes when Jung Hui, an actor, and former K-Pop idol, ends up in their doorstep claiming that Han Soo is his biological father. The family goes through thick and thin, one marriage after the other, trying to figure out why their father happens to be strange.
Na Yeong-sil has an unpleasant first encounter with Oh Bok-nyeo. Cha Jeong-hwan and Byun Hye-yeong reunite eight years after their breakup.
Determined to land a role in an upcoming miniseries, An Jung-hui searches for his biological father. Byun Mi-yeong contemplates a job offer.
Jeong-hwan and Hye-yeong share a night of passion. While trying to hide from Kim Yu-joo, Mi-yeong makes an unforgettable first impression on Jung-hui.
Byun Jun-yeong's sisters find out about his dating life. Hye-yeong feels uneasy after seeing Jeong-hwan's co-worker ask him out.
Jung-hui's honest plea earns him another audition. Yeong-sil and Bok-nyeo reach an agreement about rent. Yu-joo humiliates Mi-yeong at work.
Curious about his father, Jung-hui visits Byun Han-soo's eatery as a customer. Hye-yeong and Jeong-hwan get back together.
Jung-hui tells Han-soo who he is, and is enraged by his reaction. Jeong-hwan asks Hye-yeong to move in with him. Yu-joo takes a pregnancy test.
Yu-joo asks Jun-yeong about his family and shares big news. Using her knowledge of Park Cheol-su's secret, Byun Ra-yeong asks him for a favor.
Jung-hui ignores Han-soo's attempts to meet him. Hye-yeong discusses moving out with her parents. Yu-joo looks into Jun-yeong's family business.
Hye-yeong and Jeong-hwan begin cohabitating. Jun-yeong takes the civil service exam and vows to tell his parents about Yu-joo, who's growing impatient.
Yu-joo introduces herself to Jun-yeong's parents. A missing ring brings Yeong-sil, Bok-nyeo and their children to the police station.
With a lawsuit in hand, Hye-yeong tells Bok-nyeo to apologize to Yeong-sil. Yu-joo meets Jun-yeong's family as its newest addition.
Jeong-hwan apologizes on behalf of his mother. Jung-hui drops by Han-soo's store for a drink, but leaves enraged after seeing a joyful family dinner.
In need of real-life family experience for his role, Jung-hui makes a surprising request. The explosive secret behind Han-soo's identity is revealed.
Han-soo tries to persuade Yeong-sil into letting Jung-hui join their household. Bok-nyeo shows up unannounced to Jeong-hwan and Hye-yeong's apartment.
News of Han-soo's son is met with shock by his children. Jeong-hwan's changed entry code and attitude during a blind date makes Bok-nyeo suspicious.
Living under one roof as half-siblings, Mi-yeong avoids Jung-hui at work. Yu-joo offers Jun-yeong an alternative to looking for a home of their own.
Hye-yeong confronts Yu-joo, and Mi-yeong meets with Jun-yeong to tell him about Yu-joo's past. Ra-yeong catches Jeong-hwan and Hye-yeong together.
Mi-yeong asks for a different position. Lee Yun-seok's tragic past is explained. Yeong-sil and Bok-nyeo find out about their children's relationship.
Hye-yeong becomes the target of her family's disappointment and anger. Jung-hui's interview about his father changes Mi-yeong's mind.
Hye-yeong shocks everyone with her stance on marriage. Jeong-hwan reacts with disgust when he learns of Bok-nyeo's role in his breakup eight years ago.
Disagreeing about their future, Jeong-hwan and Hye-yeong part ways. Jung-hui treats his half-sisters to a makeover for Jun-yeong and Yu-joo's wedding.
Wanting to get away from his troubles, Jeong-hwan applies for an overseas assignment. Jung-hui and Han-soo share drinks and a heartfelt conversation.
Bok-nyeo begs for Hye-yeong's help to find Jeong-hwan. Jung-hui earns praise on set for his acting. Ra-yeong becomes Cheol-su's first girlfriend.
Hye-yeong agrees to marry Jeong-hwan, but with a catch. Jun-yeong feels unloved by Han-soo in comparison to his affection for Jung-hui.
Hye-yeong and Jeong-hwan ask for their parents' blessing. Mi-yeong stands in for an actress, with Jung-hui watching anxiously from the sidelines.
Jung-hui gets protective over Mi-yeong when she gets embroiled in dating rumors with Jin Seong-jun. Bok-nyeo gives her approval under one condition.
A formal dinner between Hye-yeong and Jeong-hwan's families ends in disaster. Jung-hui celebrates his first birthday with Han-soo's family.
Jung-hui is baffled by his feelings for Mi-yeong. Bok-nyeo and Yeong-sil make peace for Jeong-hwan and Hye-yeong's sake.
Hye-yeong and Jeong-hwan tie the knot. Cha Gyu-taek reaches a boiling point with Bok-nyeo. Mi-yeong leaves a trail of kisses on Jung-hui's face.
Bok-nyeo feels duped when Hye-yeong installs a door upstairs. Yu-joo foregoes bed rest to stay on top of work. Seong-jun asks Mi-yeong out on a date.
Han-soo becomes flustered when Jung-hui asks about his past. Bok-nyeo makes the most of her arm injury to get payback on Hye-yeong.
Jung-hui and Han-soo's story becomes public news. Hye-yeong is coerced into fulfilling Bok-nyeo's various favors inside and outside of the home.
Hye-yeong expresses disappointment in Bok-nyeo's lie and Jeong-hwan's compliance. Jung-hui's mom returns to Korea and demands to see Han-soo.
After An Su-jin barges into their home, Yeong-sil sends Han-soo away. Hye-yeong reminds Bok-nyeo of their contract. Cheol-su's father meets him halfway.
Hye-yeong rushes to Bok-nyeo's side when she calls from the hospital. Jung-hui notices striking discrepancies between Su-jin and Han-soo's stories.
Hye-yeong yells at Gyu-taek for his behavior toward Bok-nyeo. Yu-joo collapses at work. Growing more suspect, Jung-hui tests his and Han-soo's DNA.
Gyu-taek separates from Bok-nyeo and moves out. Upon receiving a copy of the DNA test in the mail, Yeong-sil rushes to Jung-hui's home.
With knowledge of the truth, Jung-hui confronts Han-soo. Hye-yeong and Jeong-hwan bring Gyu-taek home. Yu-joo reflects on her loss.
With Hye-yeong's help, Bok-nyeo initiates a plan to change Gyu-taek's mind. Jung-hui's rude remarks and their parents' reaction confuses the siblings.
Following her accidental confession, Mi-yeong takes all measures to avoid Jung-hui. Hye-yeong secretly looks into Jung-hui and Han-soo.
Jung-hui assures Mi-yeong with a story about his real father. Hye-yeong pieces together the puzzle with info on Han-soo, Yeong-sil and Yun-seok.
Cheol-su meets Ra-yeong's family. Appreciative of the love and joy he received at the Byun household, Jung-hui tells Han-soo not to turn himself in.
Hye-yeong approaches her parents with her findings. After Han-soo turns himself in, Yeong-sil tells her children all about Han-soo and Yun-seok.
Hye-yeong joins Han-soo at the station, but he refuses her counsel. Reeling from shock, Ra-yeong breaks up with Cheol-su and Mi-yeong quits her job.
Hye-yeong searches for a witness to reopen Yun-seok's case. Recognizing Jung-hui's father, a reporter publicizes details about his past and identity.
Yeong-sil asks Yu-joo to not tell the family about her doctor's visit. Seeing Han-soo's latest interview, Jung-hui gets away to check on the family.
Han-soo receives his date for trial, and Yeong-sil sets hers for surgery. Jung-hui and Mi-yeong enjoy dates away from prying eyes.
Yeong-sil secretly gets admitted for surgery with Yu-joo by her side. Yun-seok asks a former teammate and witness to testify.
Bok-nyeo and Gyu-taek rally around Hye-yeong. Jung-hui finds himself in a dating rumor with a co-star and in hot water with Mi-yeong.
Gyu-taek declares newfound appreciation for Bok-nyeo. On behalf of Yun-seok, Hye-yeong asks the judge for a chance to clear his name through a retrial.
Jung-hui asks for Mi-yeong's hand in marriage. With his recovered identity, Yun-seok walks Yeong-sil down the aisle and embarks on an adventure.
