A presidente do Nakwon Hotel, Ja Geum-sun, anseia por conhecer sua família deixada para trás há muito tempo na Coreia do Norte. Há tensão em sua família sul-coreana: seu neto Se-jun tenta vender o hotel, enquanto a neta Se-yeon luta para impedir seu irmão. Enquanto isso, alguém procura Jae-heon, um ator de teatro desconhecido, para uma tarefa incomum.

Enquanto Se-yeon tenta impedir a venda do hotel, seu ex-noivo, Dong-je, aparece. Enquanto isso, depois de aceitar a proposta de Sangcheol, Jae-heon considera quem recrutar para ajudar a cumprir sua missão. A cortina finalmente sobe em uma grande peça, criada e encenada para uma pessoa em particular.

Geum-sun cumprimenta o casal que chega, Jae-heon e Yoonhee, com um rosto cheio de emoção e emoção tocada. No entanto, cada membro da família tem suas próprias opiniões e sentimentos sobre os recém-chegados, especialmente porque Jae-heon receberá uma participação no hotel. Se-yeon leva Jae-heon em um tour por Seul, na esperança de influenciá-lo para o lado dela.

Jae-heon e Yoon-hee tentam o seu melhor para manter seu disfarce como neto de Geum-sun e sua esposa. Eles colocam seu coração e alma em atuar como Ri Moon-seong e Jang Jin-sook, tentando trazer alegria para Geum-sun, evitando as suspeitas de sua família e outros que poderiam revelar suas verdadeiras identidades.

Se-yeon persuades Geum-sun to have Jae-heon work at the hotel. Since he has plenty of experience working in part-time jobs, Jae-heon quickly adapts and shows his talents. But not everyone welcomes Jae-heon, and they are trying to make things difficult for him.

Se-jun accelerates his plan to sell the hotel. Se-yeon meets her ex-fiancé Dong-je, who owns a 4% stake and will become the casting vote for the disposal of hotel Nakwon. Meanwhile, Jae-heon, Yoon-hee, Se-yeon, and Dong-je have an unexpected dinner together.

Geum-sun holds her own farewell party, inviting the special people in her life. Se-jun, Se-gyu, and Se-yeon greet their guests at the entrance of the banquet hall. As the time of the party draws near, Jae-heon and Yoon-hee encounter some unexpected personnel working at the event.

Geum-sun hides the fact that her health is getting worse. Jae-heon and Yoon-hee begin feel guilty about their deception, as Geum-sun is treating them with love and kindness. In the meantime, Tae-joo learns the secret of Ri Moon-seong that Sang-cheol has been hiding.

Se-yeon hesitates about whether to tell Geum-sun about Jae-heon’s secret. Jae-heon feels embarrassed at Se-yeon’s awkward behavior towards him. Meanwhile, Tae-joo and the real Ri Moon-seong arrive in South Korea.

Jae-heon notices that Se-yeon and Se-jun have somewhat changed their attitude towards him. He realizes that his identity and plans has been discovered, and becomes distraught. Meanwhile, Se-jun bonds with Moon-seong and puts pressure on Se-yeon.

When Se-yeon learns about the plan, she decides to become part of it and joins Jae-heon, Yoon-hee, and Sang-cheol. The four cooperate to stop Se-jun’s plan of unveiling the real ‘Ri Moon-seong’ and to allow a happy ending to the performance.

When Se-yeon learns about the plan, she decides to become part of it and joins Jae-heon, Yoon-hee, and Sang-cheol. The four cooperate to stop Se-jun’s plan of unveiling the real ‘Ri Moon-seong’ and to allow a happy ending to the performance.

Ri Moon-seong is back. Sang-cheol informs three people that Se-jun is plotting for Geum-sun and Moon-seong to meet. To counter Se-jun’s plan and discover Moon-seong’s intentions, Se-yeon assigns a task to Jae-heon and Yoon-hee.

Jae-heon, Yoon-hee, and Sang-cheol reveal the truth to the family, except for Geum-sun. Finally, the fake grandson leaves and the real one enters, but there is an awkward silence. At that time, Jae-heon prepares another scene for Geum-sun.

Geum-sun recovers consciousness and looks for Ri Moon-seong. Family members face a dilemma on whom they should bring to Geum-sun. Se-yeon asks Jae-heon one last time to act as if he were Ri Moon-seong. However, when Jae-heon meets Geum-sun, he discloses the fact that he is not her grandson.

After Moon-seong returns from a trip with Jae-heon, Moon-seong visits Geum-sun. He resolves the misunderstandings and feelings which have been built up for decades. And finally, the curtain rises on the last scene prepared by Jae-heon, and the audience for this play is only the family of Ja Geum-sun.