Ẩn Thân

Park Hye Sook

Jun Son Rim

Uhm Tae Goo

Hwang Jae Oh

Lee Chae Young

Ran

Kim Sung Kyun

Seo Soo Hyuk [NIS team leader]

Ko Chang Seok

Seo Sang Gu [2nd lieutenant] / Seo Young Kook [Professor]

Lee Yeon Kyung

[Chi Woong and Se Woong's mother]

Park Eun Bin

Yoon Yoo Ran

Choi Woo Shik

Yoon Yoo Joon [Yoo Ran's younger brother]

Son Hyun Joo

Kim Tae Won [Colonel / 5446 Corps training chief]

Hong Kyung In

Jo Doo Suk

Yoo Jun

Lee Hae Rang [Young]

Jo Young Jin

Kim Hee Kwan

Cho Yong Jin

Se Woong