Grid

Composer

• 
  Kim Joon Seok

Director

• 
  Lee Khan

Music Editor

• 
  Jung Se Rin

Screenwriter

• 
  Lee Su Yeon

Main Role

• 
  Seo Kang Jun

  Kim Sae Ha

  Main Role
• 
  Kim Ah Joong

  Jung Sae Byeok

  Main Role
• 
  Kim Mu Yeol

  Song Eo Jin

  Main Role
• 
  Lee Si Young

  "Ghost"

  Main Role
• 
  Kim Sung Kyun

  Kim Ma Nok

  Main Role

Support Role

• 
  Jang So Yeon

  Choi Seon Wool

  Support Role
• 
  Song Sang Eun

  Chae Jong Yi

  Support Role
• 
  Heo Jun Seok

  Im Ji Yoo

  Support Role
• 
  Lee Kyu Hoe

  Han Wi Han

  Support Role
• 
  Kim Hyung Mook

  Jo Heung Shik

  Support Role
• 
  Choi Kwon

  [Special Investigation Bureau Agent]

  Support Role
• 
  Ahn Sung Bong

  [Special Investigation Bureau Agent]

  Support Role
• 
  Kim Min Song

  [Special Investigation Bureau Agent]

  Support Role
• 
  Park Jun Hyuk

  [Special Investigation Bureau agent]

  Support Role
• 
  Gong Sang Ah

  Kim Min Seon [Sae Ha's mother]

  Support Role

Guest Role

• 
  Choi Seung Hoon

  Kim Sae Ha [Young] (Ep. 1)

  Guest Role
• 
  So A Rin

  Jung Sae Byeok [Young] (Ep. 1)

  Guest Role
• 
  Hong Suk Bin

  [Stabbed cashier] (Ep. 1)

  Guest Role
• 
  Kim Ja Young

  [Caregiver] (Ep. 1)

  Guest Role
• 
  Byun Jung Hee

  [Noodle restaurant owner] (Ep. 1-3)

  Guest Role
• 
  Bae Seong Il

  [Convenience store owner] (Ep. 1, 4)

  Guest Role
• 
  Goo Jae Yeon

  [Neighborhood grandmother] (Ep. 1, 4)

  Guest Role
• 
  Jo Hee Bong

  Go Han Seung

  Guest Role
• 
  Shim Wan Joon

  [Songje Police Station Detective] (Ep. 1-2, 4, 6)

  Guest Role
• 
  Kim Young Sung

  [Songje Police Station Detective] (Ep. 1-2, 4, 6)

  Guest Role
• 
  Kim Seong In

  [Songje Police Station Detective] (Ep. 1-2, 4, 6)

  Guest Role
• 
  Ko Na Young

  [Factory worker] (Ep. 1, 7)

  Guest Role
• 
  Jung Gi Sub

  [Former Admin Bureau director] (Ep. 1, 10)

  Guest Role
• 
  Woo Soo Bin

  [Former Admin Bureau control room director] (Ep. 1, 10)

  Guest Role
• 
  Won Chun Gyu

  [Hardware store worker] (Ep. 2)

  Guest Role
• 
  Lee Jin Seung

  [ST Mulsan employee] (Ep. 2)

  Guest Role
• 
  Yoon Soo Hyuk

  [Assemblyman Kim Han Seok's aide] (Ep. 2)

  Guest Role
• 
  Joo Suk Je

  [NFS researcher] (Ep. 2, 9)

  Guest Role
• 
  Kim Shi Woo

  Kim Sae Ha [Child] (Ep. 3, 5, 8)

  Guest Role
• 
  Kim Song Il

  [Doctor] (Ep. 4)

  Guest Role
• 
  Lee Yo Sung

  Kim Jin Young (Ep. 4)

  Guest Role
• 
  Kimkwak Kyeong Hee

  [Subway station janitor] (Ep. 4-6, 8)

  Guest Role
• 
  Baek Seung Chul

  Lee Jang Hyeok [Institute of Radio Research Janitor] (Ep. 4, 7-8)

  Guest Role
• 
  Kim Ji Hoon

  Lee Shi Won [Jang Hyeok's son] (Ep. 4, 7-9)

  Guest Role
• 
  Bae Eun Woo

  [Black cap woman] (Ep. 5)

  Guest Role
• 
  Jung Won Joong

  [Minister of Commerce Industry and Energy] (Ep. 5-6)

  Guest Role
• 
  Cha Sun Woo

  Jung Him Chan [Sae Byeok's brother] (Ep. 5, 9)

  Guest Role
• 
  Kwon Hyuk

  [Admin Bureau control room chief] (Ep. 5-7, 10)

  Guest Role
• 
  Moon Hak Jin

  [Subway station employee] (Ep. 6)

  Guest Role
• 
  Myung In Ho

  [Subway station employee] (Ep. 6)

  Guest Role
• 
  Lee Hae Young

  Kwon Soo Keun [Sae Ha's father] (Ep. 7)

  Guest Role
• 
  Lim Seung Beom

  [Institute of Radio Research Employee] (Ep. 7)

  Guest Role
• 
  Kim Deok Ju

  [Orphanage teacher] (Ep. 9)

  Guest Role
• 
  Kim Sung Yong

  [Institute of Radio Research manager] (Ep. 9)

  Guest Role
• 
  Jang Eui Don

  [Institute of Radio Research executive] (Ep. 9)

  Guest Role
• 
  Kim Jong Ho

  [Institute of Radio Research executive] (Ep. 9)

  Guest Role
• 
  Park Young Bok

  [Onlooker] (Ep. 10)

  Guest Role
• 
  Na Ho Won

  [Onlooker] (Ep. 10)

  Guest Role
• 
  Nam Dong Ha

  [Sae Ha's uncle] (Ep. 10)

  Guest Role
• 
  Park Seung Tae

  [Grandmother] (Ep. 10)

  Guest Role
• 
  Lee Ki Hong

  [Mystery man] (Ep. 10)

  Guest Role
• 
  Yoo Jae Myung

  [Mystery man] (Ep. 10)

  Guest Role
• 
  Yang Eun Sol

  [Person at subway station]

  Guest Role
• 
  Seo Seung Won

  [Paramedics]

  Guest Role
• 
  Byeon Gyeong Rok

  [Control room staff (past)] (Ep. 1)

  Guest Role
• 
  Lee Chang Won Guest Role
• 
  Kwak Yeong Seon

  [NIS director] (Ep. 9)

  Guest Role