When the Phone Rings

Composer

• 
  Noh Hyeong Woo

Director

• 
  Park Sang Woo
• 
  Wi Deuk Gyu

Executive Producer

• 
  Kwon Sung Chang

Screenwriter

• 
  Kim Ji Woon

Main Role

• 
  Yoo Yeon Seok

  Baek Sa Eon

  Main Role
• 
  Chae Soo Bin

  Hong Hui Ju

  Main Role
• 
  Heo Nam Jun

  Ji Sang U

  Main Role
• 
  Jang Gyu Ri

  Na Yu Ri

  Main Role

Support Role

• 
  Han Jae Yi

  Hong In A [Hong Il Gyeong's eldest daughter]

  Support Role
• 
  Jung Dong Hwan

  Baek Jang Ho [Baek Sa Eon's grandfather]

  Support Role
• 
  Yoo Sung Joo

  Baek Eui Yong [Baek Sa Eon's father / Presidential candidate]

  Support Role
• 
  Chu Sang Mi

  Sim Gyu Jin [Baek Sa Eon's mother / Negotiation expert]

  Support Role
• 
  Choi Kwang Il

  Hong Il Gyeong [Chairman of Cheongwoon Ilbo]

  Support Role
• 
  Oh Hyun Kyung

  Kim Yeon Hui [Hong Il Gyeong's 2nd wife]

  Support Role
• 
  Im Chul Soo

  Kang Yeong U [Spokesperson Office manager]

  Support Role
• 
  Choi Woo Jin

  Park Do Jae [Spokesperson Office special admin. officer]

  Support Role
• 
  Park Sun Young

  Kim Su Yeong [Spokesperson Office admin. officer]

  Support Role
• 
  Song Jin Hee

  An Jin Hui [Spokesperson Office admin. officer]

  Support Role
• 
  Jung Ji Hwan

  Jung Won Bin [Sign language interpreter for President Office]

  Support Role
• 
  Ko Sang Ho

  Jang Hyeok Jin [Reporter covering presidential office / Former war correspondent]

  Support Role
• 
  Kim Tae Han

  Jung Sang Hun / Jung Jin Seok [Fishing spot owner]

  Support Role
• 
  Hong Seo Joon

  Min Do Gi [Baek Eui Yong's butler and personal secretary]

  Support Role
• 
  Yang Jo Ah

  Han Jin [Sign language interpretation center director]

  Support Role
• 
  Kang Hyeon U

  Lee Tae Yeong

  Support Role
• 
  Park Jae Yun

  [Hijacker]

  Support Role

Guest Role

• 
  Son Ki Chul

  [Reporter] (Ep. 1)

  Guest Role
• 
  Tak Seung Bin

  [HBC staff] (Ep. 1)

  Guest Role
• 
  Park Gang To

  [HBC staff] (Ep. 1)

  Guest Role
• 
  Kim Jin

  [Interpreter] (Ep. 1)

  Guest Role
• 
  Lee Bum Chan

  [HBC staff director] (Ep. 1)

  Guest Role
• 
  Lee Gyoung Ho

  [HBC staff director] (Ep. 1)

  Guest Role
• 
  Kim Mi Ran

  Lee Jeong Won [Bodyguard] (Ep. 1-2)

  Guest Role
• 
  Lee Seung Jin

  [Reporter HBC] (Ep. 1, 3)

  Guest Role
• 
  Park Geon Rak

  Director Yun (Ep. 1, 7, 12)

  Guest Role
• 
  Kaare Svejgaard Olsen

  [Ambassador] (Ep. 1, 9)

  Guest Role
• 
  Ra Lee Hye Jin

  Park Hyeon Jin [Bodyguard assigned to Hui Ju] (Ep. 2)

  Guest Role
• 
  Lee Hyun

  [Defendant] (Ep. 2)

  Guest Role
• 
  Lee Heung Yun

  [Plaintiff] (Ep. 2)

  Guest Role
• 
  Kim Gyu Do

  [Prosecutor] (Ep. 2)

  Guest Role
• 
  Lee Seo Won

  [Nurse] (Ep. 2-3)

  Guest Role
• 
  Park Won Sang

  Na Jin Cheol [Hui Ju's biological father / Former club host] (Ep. 2-4, 9, 12]

  Guest Role
• 
  Yeo Min Goo

  [Arsonist] (Ep. 3)

  Guest Role
• 
  Kim Min Suk

  [Detective] (Ep. 3)

  Guest Role
• 
  Jung Eun Ran

  [Caregiver] (Ep. 3)

  Guest Role
• 
  Kim Moon Soo

  [Government official] (Ep. 3)

  Guest Role
• 
  Kim Soo Jung

  [Government official's wife] (Ep. 3)

  Guest Role
• 
  Bae Seong Il

  Park Sang Uk [Police officer] (Ep. 3-4)

  Guest Role
• 
  Song Young Ah

  Kim Jeong Yeon [Police officer] (Ep. 3-4)

  Guest Role
• 
  Min Eung Shik

  [Government official] (Ep. 3-5)

  Guest Role
• 
  Kang Ji Yong

  Ji Sang U [Young] (Ep. 3, 5-6)

  Guest Role
• 
  Song Hoon

  Han [HBC PD] (Ep. 3, 7)

  Guest Role
• 
  Lee Yoon Soo

  [HBC staff] (Ep. 3, 7)

  Guest Role
• 
  Lee Si On

  [Mysterious child in mansion] (Ep. 3, 5-6, 8-10)

  Guest Role
• 
  Shin Yeon Woo

  Hong Hui Ju [Young] (Ep. 3-8, 11-12)

  Guest Role
• 
  Hyun Seo Young

  Sin Jung Min (Ep. 4)

  Guest Role
• 
  Hwa Sung

  [Hair stylist] (Ep. 4)

  Guest Role
• 
  An Tae Gyeong

  [Restaurant staff] (Ep. 4)

  Guest Role
• 
  Kim Seung Jun

  [President Office's interviewer] (Ep. 4)

  Guest Role
• 
  Park Gyeong Eun

  [Sign language applicant] (Ep. 4)

  Guest Role
• 
  Lee Su Jin

  [Event attendee] (Ep. 4)

  Guest Role
• 
  Han Chae Bin

  [Event attendee] (Ep. 4-5)

  Guest Role
• 
  Son Ye Ji

  [Event attendee] (Ep. 4-5)

  Guest Role
• 
  Park Chang Hoon

  [Sign language applicant] (Ep. 4-6, 8)

  Guest Role
• 
  Yoon Seo Yeon

  Hong In A [Young] (Ep. 4-8, 10, 12)

  Guest Role
• 
  Lee Jae Joon

  Baek Sa Eon [Young] (Ep. 4-12)

  Guest Role
• 
  Hwang Jung Yoon

  [Saleswoman] (Ep. 5)

  Guest Role
• 
  Jwa Chae Won

  [Saleswoman] (Ep. 5)

  Guest Role
• 
  Kim Yu Ri

  Kim Tae Gyeong (Ep. 5-6, 8)

  Guest Role
• 
  Kim Young Mi

  [Seongnang-gu Sign Language Center interpreter] (Ep. 5, 8-9, 12)

  Guest Role
• 
  Kim Geum Hui

  [Seongnang-gu Sign Language Center interpreter] (Ep. 5, 9, 12)

  Guest Role
• 
  Seo Eun Joo

  [Hiker] (Ep. 6)

  Guest Role
• 
  No Soo Sung

  [Hiker] (Ep. 6)

  Guest Role
• 
  Jin Sung Min

  [Paramedic] (Ep. 6)

  Guest Role
• 
  Park Hwa Hong

  [Paramedic] (Ep. 6)

  Guest Role
• 
  Kim Deok Ju

  [Nun] (Ep. 6, 8-9)

  Guest Role
• 
  Lee Ju Mi

  [Lobby patient] (Ep. 7)

  Guest Role
• 
  Choi Yo Woon

  [Lobby patient] (Ep. 7)

  Guest Role
• 
  Park Seon Ok

  [Lobby patient] (Ep. 7)

  Guest Role
• 
  Oh Seung Ah

  [Character in makjang drama] (Ep. 7)

  Guest Role
• 
  Seo Ye Bin

  (Ep. 7)

  Guest Role
• 
  Lee Doo Suk

  Kang Hyeong Cheol [Detective] (Ep. 7, 10-11)

  Guest Role
• 
  Ahn Chan Woong

  [Ui Yong's aide] (Ep. 7-9, 11-12)

  Guest Role
• 
  Hong Suk Youn

  [Delivery man] (Ep. 8)

  Guest Role
• 
  Jo Min Jae

  [PD] (Ep. 9)

  Guest Role
• 
  Park Da On

  Park Do Jae [Young] (Ep. 10)

  Guest Role
• 
  Lee Seung Joon

  [Judge] (Ep. 12)

  Guest Role
• 
  Heo Soo Bin

  [Waitress] (Ep. 12)

  Guest Role
• 
  Kim Doo Eun

  [Deliveryman] (Ep. 12)

  Guest Role
• 
  Jaspreet Kaur

  [Kidnapped woman] (Ep. 12)

  Guest Role
• 
  Kang Do Yoon

  [Soldier] (Ep. 12)

  Guest Role