Ji Chang Wook
Ma Dong Chan
Papel principal
Won Jin Ah
Go Mi Ran
Papel principal
Yoon Se Ah
Na Ha Young
Papel principal

Im Won Hee
Son Hyun Ki [Producer]
Papel secundario
Shim Hyung Tak
Hwang Byung Shim / Hwang Dong Hyuk [Mi Ran’s ex-boyfriend / College professor]
Papel secundario
Kim Won Hae
Ma Dong Shik [Dong Chan's younger brother] | Ma Pil Go [Dong Chan's father] (Ep. 2)
Papel secundario
Jun Soo Kyung
Ma Dong Joo [Dong Chan's sister]
Papel secundario
Yoon Seok Hwa
Kim Won Jo [Dong Chan’s mother]
Papel secundario
Jung Hae Kyun
Kim Hong Seok [CEO of TV Show broadcasting]
Papel secundario
Park Choong Seon
Go Yoo Han [Mi Ran's father]
Papel secundario
Kil Hae Yeon
[Mi Ran's mother]
Papel secundario
Seo Hyun Chul
Hwang Gap Soo [Bio-research professor]
Papel secundario
Seo Jung Yeon
Oh Young Sun [Byung Shim's wife]
Papel secundario
Park Hee Jin
Park Kyung Ja [Mi Ran's friend]
Papel secundario
Oh Ah Rin
Ma Seo Yoon [Dong Shik's daughter]
Papel secundario
Lee Moo Saeng
Jo Ki Beom [Gap Soo's aide]
Papel secundario
Yoon Na Moo
Go Nam Tae [Mi Ran's little brother]
Papel secundario
Choi Bo Min
Hwang Ji Hoon [College Student / Byung Shim's son]
Papel secundario
Kang Yoo Seok
Park Young Joon [Hwang Ji Hoon's friend]
Papel secundario
Hong Seo Baek
Producer Lee
Papel secundario
Han Jae Yi
PD So
Papel secundario
Nam Min Woo
Kim Ji Oh [PD]
Papel secundario
Lee Do Yup
Baek Yeong Tak [Detective / Dong Joo's ex-husband]
Papel secundario
Kim Bup Rae
Lee Seok Du / Lee Hyeong Du [CEO of Unsung group]
Papel secundario
Jun Byung Wook
[Seok Du's secretary]
Papel secundario
Lee Bong Ryung
Park Yoo Ja [Fortuneteller]
Papel secundario
Kim Min Chul
[Teacher Assistant]
Papel secundario
Lee Joo Young
Lee Hye Jin [Dong Sik's wife]
Papel secundario

L.Joe
Kim Jin [1999's Hyun Gi's aide] (Ep. 1-2, 10)
Invitado
Lee Hong Ki
Son Hyun Gi [1999 self] (Ep. 1-2, 10)
Invitado
Baro
Hwang Byung Shim [1999 self] (Ep. 1-2)
Invitado
Chae Seo Jin
Na Ha Young [1999 self] (Ep. 1-3)
Invitado
Oh Ha Nee
Park Kyung Ja [1999 self] (Ep. 1-4, 11)
Invitado
Song Ji Eun
Oh Young Sun [1999 self] (Ep. 1-4)
Invitado
Kang Ki Doong
Ma Dong Shik [1999 self] (Ep. 2, 11)
Invitado
Han Da Sol
Ma Dong Joo [1999 self] (Ep. 2)
Invitado
Lee Do Gyeom
Baek Yeong Tak [1999 self] (Ep. 1-2)
Invitado
Park Min Soo
Go Nam Tae [Child] (Ep. 1-3)
Invitado
Ahn Tony
Himself [Award show MC] (Ep. 1)
Invitado
Robin Deiana
Nikolai [Killer] (Ep. 1)
Invitado
Kim Wook
Jo Ki Beom [1999 self] (Ep. 1-3)
Invitado
Choi Ri
[Woman who rides water-bike with Byung Shim] (Ep. 1)
Invitado
Seo Sang Won
Dr. Yoon (Ep. 3-4, 6, 12)
Invitado
Im Jae Geun
[Music store owner] (Ep. 3)
Invitado
Choi Na Moo
[Police officer] (Ep. 3)
Invitado
Yang Hyun Min
[Thug] (Ep. 5-6)
Invitado
Ra Mi Ran
Kang Ok Bong [Panelist] (Ep. 6)
Invitado
Kim Soo Ro
Yoo Ji Min [Panelist] (Ep. 6)
Invitado
Jeong Myung Jun
Yoo Woo Jun [Panelist] (Ep. 6)
Invitado
Jung Sung Ho
[Debate show MC] (Ep. 6)
Invitado
Kwon Hyuk Soo
[President of South Korea] (Ep. 6)
Invitado
Kim Jong Goo
Kim Shi Seok [Hong Seok's boss] (Ep. 7-8, 12)
Invitado
Yoon Joo Man
Terry Kim / Kim Hyeon Do [Lee Seok Du's Hitman] (Ep. 7, 9-12, 14-15)
Invitado
Han Ki Woong
Lee Jung Woo [Lee Seok Du's son] (Ep.12-13)
Invitado
Park Jin Young
Jang Woo Shin [Man who wants to go inside the cryonic capsule] (Ep.14)
Invitado
Choi Dae Sung
Kim Jin [Present Self]
Invitado
Yeom Dong Hun
Seo Yoon Suk [professor]
Invitado
Jang Ye Rim
[Experiment woman]
Invitado
Joo Byung Ha
[Police officer]
Invitado
Amy Aleha
[News anchor]
Invitado
Kang Ro Chae
Nurse Seol Soo Jin
Invitado
Henny Savenije Invitado
Lee Gyoo Seop Invitado
Kim Do Won
[Telescope kid]
Invitado
Nam Ga Seol
[Young Joon's fling]
Invitado
Song Hoon
[Ma Dong-Ju's ex-husband]
Invitado
Kim Jae Cheol
Reporter Kim Wu Se, Wonders Media (Ep 6)
Invitado
Choi Soo Hyun
[Nurse]
Invitado
Lee Kwang Ik
[Employee]
Invitado