Seo In-guk (born October 23, 1987), is a South Korean singer-songwriter and actor. He began his singing career after winning the talent reality show Superstar K in 2009, and made his acting breakthrough in Reply 1997 (2012). Since then, he has starred in television series, High School King of Savvy (2014), Hello Monster (2015), Shopping King Louie (2016), and Death's Game (2023).

Filmography

• The Office Worker Who Sees Destiny — Choi Young-hoon
• 2026Boy — Mad Hatter
• Boyfriend on Demand — Park Kyeong-nam
• See You at Work Tomorrow! — Kang Si-woo
• Twelve — Won-seung
• Death's Game — Choi Yee-jae
• 2023TRAP by SEO IN GUK — Director
• 2023The Boys — Lee Jae-seok
• Café Minamdang — Nam Han-jun
• 2022Project Wolf Hunting — Park Jong-du
• Soundtrack #1 — Jay Jun
• Doom at Your Service — Myul Mang / Kim Sa-ram
• Navillera — Hwang Hee
• 2021Pipeline — Pindol / Kang Sae-dol / Drill-bit
• Abyss — Grim Reaper
• The Smile Has Left Your Eyes — Kim Moo-Young
• 2016I Love That Crazy Little Thing — Yang Ming-zhe
• Shopaholic Louis — Louie
• Squad 38 — Yang Jung-do
• Hello Monster — Lee Hyun
• Oh My Ghost — Edward
• Another Parting — Ahn Young Mo
• High School King of Savvy — Lee Min-seok / Lee Hyung-seok
• The King's Face — Prince Gwanghae
• Master's Sun — Kang-woo
• 2013No Breathing — Jo Won-il
• Reply 1994 — Yoon Yoon-jae
• Love Rain — Kim Chang-mo & Kim Jeon-seol
• Reply 1997 — Yoon Yoon-jae
• 아들 녀석들 — Yoo Seung-Gi
• Law of the Jungle
• Running Man
• KBS Entertainment Awards — Host
• KBS Drama Awards — Host

Appearances as themselves (15)

• Better Late Than Single: After Service — Self
• Better Late Than Single — Self - Cupid Expert
• Here for Promo — Self
• Jungle Bob — Self
• ZIP DAESUNG — Self
• Nattering with Nah — Self
• The Seasons — Self
• Look, My Shoulder's Dislocated — Self
• She Was Pretty — Self
• Home Alone — Self
• 2013SBS: The Master's Sun - Making — Self
• Baeksang Arts Awards — Self
• SNL Korea — Self
• Superstar K — Self - Participant
• You Hee-yeol's Sketchbook — Self