Reply 1997 is a 2012 South Korean television series that follows the lives of six friends in Busan as the timeline shifts between their past as 18-year-old high schoolers in 1997 and they're present as 33-year-olds at their high school reunion dinner in 2012, where one couple announces their engagement. As the first installment of the Reply series, it also depicts the extreme fan culture that arose in the 1990s, when first-generation idol groups like H.O.T. and Sechs Kies took center stage and K-pop was just getting started. The series is one of the highest-rated Korean dramas in cable television history and has garnered praise from audiences and critics for being well-researched, refreshing, genuine, and full of humor and heart. The series originally aired live on cable channel tvN in 16 episodes.

In this film, Seo In-guk plays Yoon Yoon-jae, Shi-won's childhood best friend who frequently visits her house following the death of his parents. Yoon Yoon-jae is quiet and brooding yet devoted to those close to him. He is also known as one of the two most attractive boys in the school, along with Joon-hee, and girls frequently fall for both of them. He is bright and graduated first in his class. Yoon-jae falls in love with Shi-won as a teenager and tries to keep it a secret. Seo In-guk received the Rising Star Award at the 1st K-Drama Star Awards, and Reply 1997 received the Grand Prize (Daesang) at the 7th Cable TV Broadcasting Awards.

Detailed information:
Directed by: Shin Won-ho
Starring: Jung Eun-ji, Seo In-guk, Hoya, Eun Ji-won, Shin So-yul, Lee Si-eon
Release date: July 24, 2012

No Breathing is a 2013 South Korean sports film starring Seo In-guk, Lee Jong-suk, and Kwon Yuri set in the world of competitive swimming. In Guk plays Won Il in this film, who quit swimming due to personal tragedies. He is a headstrong, impulsive, in-the-moment type of guy.

On May 19, 2013, the filming began. One of the locations was Davao, Philippines, where the overseas field training scenes and the movie poster were shot. On October 30, 2013, the film was released in theaters. No Breathing opened to 44,707 admissions on October 30, 2013, and ranked fourth at the Korean box office. During its domestic run, the film sold 451,669 tickets and grossed $2,991,824,739. The film grossed more than $22,655 in its first weekend in Singapore and $38,740 during its two-week run. It grossed $35,728 in its first weekend in Hong Kong and a total of $53,729 at the end of its run.

Detailed information:
Directed by: Jo Yong-sun
Starring: Lee Jong-suk, Seo In-guk, Kwon Yuri
Release date: October 30, 2013
Running time: 118 minutes

High School King of Savvy is a South Korean television series that premiered in 2014 and starred Seo In-guk, Lee Ha-na, Lee Soo-hyuk, and Lee Yul-eum. Lee Min-suk (Seo In-guk) is a varsity ice hockey player and a high school student. Despite their nine-year age difference, he and his older brother Hyung-suk look strikingly similar. Min-suk is forced to pretend to be a high-ranking executive at an IT conglomerate after receiving a mysterious phone call from Hyung-suk instructing him to impersonate his brother at the latter's new job. Living a double life while unaware of the rules within the Korean workplace, Min-suk learns how to navigate his way in the world of adults with the help of Jung Soo-young (Lee Ha-na), a temp with an odd personality whom he eventually falls in love with.

On April 25, 2014, the first script reading took place at the CJ E&M Centre in Sangam-dong, Seoul, South Korea. Filming began in early May 2014. From June 16 to August 11, 2014, it aired 17 episodes on tvN on Mondays and Tuesdays at 23:00 (KST). Seo In-guk was nominated for the Excellence Award for Actor at the 7th Korea Drama Awards.

Detailed information:
Directed by: Yoo Je-won
Starring: Seo In-guk, Lee Ha-na, Lee Soo-hyuk, Lee Yul-eum
Release date: June 16, 2014

The King's Face is a South Korean television series that premiered in 2014. It stars Seo In-guk, Jo Yoon-hee, Lee Sung-jae, Kim Gyu-ri, and Shin Sung-rok. It aired on KBS2 from November 19, 2014 to February 5, 2015 at 21:55 on Wednesdays and Thursdays. Seo In-guk was named Best New Actor at the KBS Drama Awards.

Seo In-guk plays Prince Gwanghae in this film. Gwanghae, the child of a concubine, ascends to the throne of Joseon. For the next 16 years, the illegitimate prince must deal with death threats and the possibility of dethronement. Gwanghae has a strained relationship with his father, King Seonjo, and the two eventually become political and romantic rivals. Gwanghae enlists the help of a face-reading fortuneteller to help him become the next King, using physiognomy as a weapon and means of gaining power.

Detailed information:
Directed by: Yoon Sung-sik, Cha Young-hoon
Starring: Seo In-guk, Jo Yoon-hee, Lee Sung-jae, Kim Gyu-ri, Shin Sung-rok
Release date: November 19, 2014

Hello Monster is a South Korean television series starring Seo In-guk, Jang Na-ra, Choi Won-young and Park Bo-gum. From June 22 to August 11, 2015, it aired every Monday and Tuesday at 21:55 on KBS2. Despite the show's low ratings, audiences and critics alike praised its story and the cast's performances, particularly Park Bo- gum's.

Seo In-guk plays Lee Hyun in this film. Lee Hyun was a "strange child" who piqued the interest of his father, a police inspector, who eventually confined him in a small room to keep him from breeding criminal thoughts. He is a bright child who goes on to study abroad and become a well-known professor. He mysteriously loses his childhood memories, and a series of events forces him to return to South Korea. There, he tries to solve a series of murders that appear to be connected in order to find his long-lost little brother, whom he believes is the serial killer.

Detailed information:
Directed by: Noh Sang-hoon, Kim Jin-won
Starring: Seo In-guk, Jang Nara, Choi Won-young, Park Bo-gum
Release date: June 22, 2015

Squad 38 is a South Korean television series starring Ma Dong-seok, Seo In-guk and Choi Soo-young. From June 17, 2016 to August 6, 2016, it aired on the cable network OCN on Fridays and Saturdays at 23:00 (KST) for 16 episodes. The plot revolves around civil servant Baek Sung-il and his team, who work with the fraud Yang Jeong-do to collect taxes from habitual tax evaders and delinquent taxpayers.

Squad 38 is motivated and has received advice from the Seoul Metropolitan Government's "38 Tax Collection Division". On March 3, 2016, the main cast of the series was revealed. On March 19, 2016, the first script reading took place at the CJ E&M Centre in Sangam-dong, Seoul, South Korea. Yang Jeong-do, a professional swindler, is played by Seo In-guk in this film. Seo In-guk received the Special Award for Actor at the 11th Asian TV Drama Conference.

Detailed information:
Directed by: Han Dong-hwa
Starring: Ma Dong-seok, Seo In-guk and Choi Soo-young
Release date: June 17, 2016

Shopping King Louie is a South Korean drama starring Seo In-guk, Nam Ji-hyun, Yoon Sang-hyun and Im Se-mi. From September 21 to November 10, 2016, it aired on MBC on Wednesdays and Thursdays at 22:00 (KST). A romantic comedy about Louis (Seo In-guk), a wealthy heir who spends his money on anything with a subtle beauty speaking to his soul. He loses his memory one day and meets Bok-Shil (Nam Ji-hyun), a pure and energetic rural woman. His spending habits initially astound her. In the process of teaching him to only buy bare necessities or inexpensive small kindnesses that lighten up one's day, she also learns that bare necessities are not the same for everyone as they depend on everyone's own values that shape their lives and thus their shopping patterns. Both have innate innocence which brings them to care for each other, leading to undeniable love.

Seo In-guk plays Louis, the last surviving heir of a chaebol chairman, in this film. He seeks retail therapy to alleviate his loneliness after growing up in a sheltered and pampered environment in France. Seo In-guk won the Excellence Award for Actor in a Miniseries at the 35th MBC Drama Awards.

Detailed information:
Directed by: Lee Sang-yeob
Starring: Seo In-guk, Nam Ji-hyun, Yoon Sang-hyun and Im Se-mi
Release date: September 21, 2016

The Smile Has Left Your Eyes is a South Korean television series that premiered in 2018 and stars Seo In-guk, Jung So-min, and Park Sung-woong. It is a remake of the Japanese television series Sora Kara Furu Ichioku no Hoshi, which aired in 2002. It aired on tvN on October 3, 2018, at 21:30 KST on Wednesdays and Thursdays. Early in July 2018, the first script reading took place at Sangam DDMC in Sangam-dong, Seoul.

This 2018 Korean drama revolves around Kim Moo Young (Seo In-guk), a complex, mysterious man with a forgotten past. He meets and falls in love with Yoo Jin-Kang (Jung So-min), and despite her initial negative impression of him, she later discovers that Moo-young is innocent and struggling to recognize his past life. Yoo Jin Gook (Park Sung-woong), a homicide detective, suspects Moo-Young is more sinister than he lets on, completely unaware that he is the key to both Moo-Young and Jin-intertwined Kang's history. The situation becomes more complicated when Moo-young regains his memories, leading him to discover the truth about his father's death and other details.

Detailed information:
Directed by: Yoo Je-won
Starring: Seo In-guk, Jung So-min, and Park Sung-woong
Release date: October 3, 2018

Doom at Your Service is a 2021 South Korean television series starring Park Bo-young and Seo In-guk. From May 10 to June 29, 2021, it aired on tvN. The series has already been pre-sold in 150 countries. It can be viewed on various platforms, including Viki, Viu, U-Next in Japan, iQIYI in Taiwan, and Now TV in Hong Kong. It will also be broadcast on Mnet Japan beginning October 23, 2021. This drama was ranked 10th in the category of The 10 best Korean dramas of 2021 by NME in 2021.

Seo In-guk plays Myul Mang in this film, a messenger between gods and humans who simply follows fate with no intention or passion. He was born somewhere between the dark and the light. Countries vanish when he breathes, seasons collapse when he walks, and life is extinguished when he smiles. All he has to do is exist for something to go wrong. He decides to end the world and thus bring doom upon himself after growing tired of his immortal life of bringing misfortune and destruction.

Detailed information:
Directed by: Kwon Young-il
Starring: Park Bo-young and Seo In-guk
Release date: May 10, 2021

Master's Sun is a South Korean television series that premiered in 2013 and starred So Ji-sub and Gong Hyo-jin. Joo Joong-won (So Ji-sub) is the cold and distant CEO of Kingdom, which owns a major department store and a hotel. He meets the depressed Tae Gong-shil (Gong Hyo-jin), who began seeing ghosts following an accident. Their lives change when they discover that whenever Gong-shil touches Joong-won, the ghosts that surround her vanish. Gong-shil agreed to let her stay by Joong-won's side in exchange for helping him recover a fortune stolen from him during a kidnapping attempt. The horror-romantic comedy is written by the Hong Sisters, and aired on SBS from August 7 to October 3, 2013, on Wednesdays and Thursdays at 21:55 for 17 episodes.

Seo In Guk plays Kang Woo, a former soldier who served in the South Korean Army's Zaytun Division, which was deployed to Iraq in the mid-2000s. Seo In-guk won the New Star Award at the SBS Drama Awards as a result of this film. He was also named Most Popular Actor at the 50th Baeksang Arts Awards.

Detailed information:

Directed by: Jin Hyuk

Starring: So Ji-sub, Gong Hyo-jin

Release date: August 7, 2013