Directed by
| Kae-Byeok Lee | ... | (as Gye-byeok Lee) |
Writing Credits (in alphabetical order)
| Bang Woo-ri | ... | (adaptation) (as Woo-ri Bang) |
Cast (in credits order)
| Cha Seung-won | ... | Cheol-Soo (as Seung-Won Cha) | |
 |
Chae-Young Um | ... | Saet-Byeol |
| Park Hae-joon | ... | Young-Soo | |
| Kim Hye-Ok | ... | Saet-Byeol's Grandmother | |
| Jeon Hye-bin | ... | Eun-Hee | |
| Jo Han-chul | ... | Duk-Goo | |
| Yoon Byung-hee | ... | Duk-Chang | |
|
|
Seung-won Lee | ... | Duk-Soo |
|
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Kim Pub-lae | ... | Yang Doo-Mok (as Pub-lae Kim) |
|
|
Sung Ji-ru | ... | Jung-Kwon (as Ji-ru Sung) |
| Shin Hyeon-bin | ... | Hye Young | |
|
|
Lee Seung-Yuop | ... | Self |
| Ahn Kil-kang | ... | Mr. Kim | |
|
|
Han Bi Ryu | ... | Min-Jung |
| Rest of cast listed alphabetically: | |||
|
|
So Ah-Rin | ... | Middle school Saet-byeol, kalguksu |
| Ji E-Suu | ... | Ji-an | |
| Jung Joon-won | ... | Choong-Sik (as Joon-Won Jung) | |
| Goo Joon-woo | ... | Kid patient 2 | |
|
|
Nam Tae-boo | ... | Guest 2 from Kalguksu (as Tae-boo Nam) |
Produced by
| Jennice Lee | ... | development producer: Dexter Studios |
Visual Effects by
| Deokmun Jeong | ... | fx lead artist |
| Jung-hoon Kim | ... | visual effects supervisor |
| Jinhee Kim | ... | visual effects producer (uncredited) |
| Sung-min Alvin Yun | ... | visual effects supervisor (uncredited) |
Editorial Department
| Heeyeun Shin | ... | digital intermediate producers |
Music Department
| Hyun Seo-won | ... | composer additional music |
