Kim Soo-hyun as Won Ryu-hwan / Bang Dong-gu

Park Ki-woong as Lee Hae-rang

Lee Hyun-woo as Lee Hae-jin

Son Hyun-joo as Kim Tae-won

Ko Chang-seok as Seo Sang-gu

Kim Sung-kyun as Seo Soo-hyuk

Shin Jung-keun as Mr. Park

Hong Kyung-in as Jo Doo-seok

Lee Chae-young as Ran

Park Eun-bin as Yoon Yoo-ran

Choi Woo-shik as Yoon Yoo-joon

Goo Seung-hyun as Hwang Chi-woong

Um Tae-goo as Hwang Jae-oh

Kim Pub-lae as NIS General Manager

Park Hye suk as Jeon Sun-im

Jo Yong jin as Se-yoong

Jo Young-jin as Kim Hui-gwan

Lee Yeon-kyung as Chi-woong's Mother

Ko In-beom as NIS

Yoo Jun as Young Lee Hae-rang