| Person | Type | Job | Role(s) | Episodes |
|---|---|---|---|---|
 Kwon Do-eun | Crew | Writing | Writer, Creator | 16 |
 Jung Jee-hyun | Crew | Directing | Director, Creator | 16 |
Kim Seung-ho | Crew | Directing | Co-Director | 16 |
 Lim Ha-young | Crew | Sound | Music | 16 |
Kim Young-kyu | Crew | Production | Executive Producer | 16 |
 Jeon Soo-hwan | Cast | Actor | Mr. Kim | 1 |
 Kim Tae-ri | Cast | Actress | Na Hee-do | 16 |
 Shin Yeon-sook | Cast | Actress | Hee-do's grandmother | 2 |
 Kim Young-sun | Cast | Actress | Yi-jin's mother | 16 |
 Choi Tae-joon | Cast | Actor | Jung Ho-jin | 2 |
 Choe Min | Cast | Actor | Fencing coach | 1 |
Nam Dong-ha | Cast | Actor | Disciplinary committee member | 1 |
 Nam Joo-hyuk | Cast | Actor | Baek Yi-jin | 16 |
 Joo Bo-young | Cast | Actress | Lee Ye-ji | 16 |
 Bona | Cast | Actress | Ko Yu-rim | 16 |
 Kim Hye-eun | Cast | Actress | Yang Chan-mi | 16 |
 Son Young-soon | Cast | Actress | Bus passenger | 1 |
 Jo Nam-hee | Cast | Actor | Taeyang High School headmaster | 2 |
 Cha Mi-kyeong | Cast | Actress | Victim's mother | 1 |
 Yu Bee | Cast | Actor | Yi-jin's friend | 1 |
 Park Eun-young | Cast | Actress | Neighbourhood woman | 1 |
 Kim Nam-hee | Cast | Actor | Cellphone store employee | 1 |
 Yoon Se-woong | Cast | Actor | Seo Yeong-seong | 4 |
 Heo Ji-na | Cast | Actress | Yu-rim's mother | 16 |
 Lee Jong-goo | Cast | Actor | Diner | 1 |
 Lee Jun-hee | Cast | Actor | Ha Byung-jin | 1 |
 Choi Myeong-been | Cast | Actress | Kim Min-chae | 16 |
 Jung Hyeong-seok | Cast | Actor | Kim Hak-gyu | 8 |
 Go Dong-eop | Cast | Actor | Diner | 1 |
 Ok Ye-rin | Cast | Actress | Na Hee-do (young) | 3 |
 Jung Yoo-min | Cast | Actress | Hwang Bo-mi | 1 |
 Lee Joong-ok | Cast | Actor | Fencing club coach | 2 |
 Ok Joo-ri | Cast | Actress | Ahyeon Supermarket owner | 5 |
 Kang Hak-soo | Cast | Actor | Loen Hotel employee | 1 |
 Lee Seon-gu | Cast | Actor | National fencing team coach | 4 |
 Bang Eun-jeong | Cast | Actress | Lee Da-seul | 3 |
 Park Ki-deok | Cast | Actor | Lee Gi-hun | 2 |
 Park Yoon-hee | Cast | Actor | Baek Sung-hak | 16 |
 Choi Kyo-sik | Cast | Actor | Neighbourhood man | 1 |
 Jang Jun-hyeon | Cast | Actor | Yi-jin's acquaintance / Director of Han River C&T | 1 |
 Kang Hoon | Cast | Baek Yi-hyun (adult) | 1 | |
 Song Yo-sep | Cast | Actor | MBS TV network department head | 1 |
 Lee Si-hoo | Cast | UBS Network cameraman | 2 | |
 Jung Chung-gu | Cast | Actor | Myeongjin Book Rentals owner | 3 |
 So Hee-jung | Cast | Actress | Seung-wan's mother | 16 |
Na Ho-won | Cast | Actor | Bus driver | 1 |
 Kim Nam-yee | Cast | Actress | Yi-jin's paternal aunt | 1 |
 Bae Hyun-kyung | Cast | Actor | UBS Network Sports department staff | 1 |
 Choi Nam-wook | Cast | Actor | Fencing association employee | 1 |
 Kim Seong-yong | Cast | Actor | Disciplinary committee member | 1 |
 Bae Seong-il | Cast | Actor | Mr. Baek's ex-employee | 2 |
 Park Yong | Cast | Actor | 9/11 survivor | 1 |
 Kang Moon-kyung | Cast | Actor | UBS director 2009 | 1 |
 Kim Mi-hye | Cast | Actress | Shin Jae-kyung (young) | 1 |
 Byun Yun-jeong | Cast | Actress | Ji-woong's mother | 1 |
 Kim Joo-ah | Cast | Actress | Sophia Choi | 1 |
 Kim Ji-ho | Cast | Actor | MBS TV network employee | 1 |
 Koo Ja-geon | Cast | Actor | Job interviewee | 1 |
 Bae Ki-beom | Cast | Actor | Upset diner | 1 |
 Park Yoon | Cast | Actress | Jung Da-yeong | 5 |
 Ri Min | Cast | Chinese restaurant owner | 1 | |
 Kim So-hyun | Cast | Actress | Na Hee-do (adult) | 16 |
 Choi Hyun-wook | Cast | Actor | Moon Ji-woong | 16 |
 Lee Jae-woo | Cast | Actor | Photo studio owner | 1 |
 Lee Joo-myung | Cast | Actress | Ji Seung-wan | 16 |
 Kim Dong-gyun | Cast | Actor | Yu-rim's father | 16 |
 Yoon Ju-man | Cast | Actor | PD Park | 2 |
 Baek Ji-hye | Cast | Actress | Kim Da-mi | 1 |
 Park Jeong-pyo | Cast | Actor | Yi-jin's maternal uncle | 4 |
 Moon Woo-bin | Cast | Actress | Kang Ji-soo | 3 |
 Choi Min-yeong | Cast | Actor | Baek Yi-hyun | 16 |
 Son Dong-soo | Cast | Actor | Sports agency employee | 1 |
 Lee Kyung-oh | Cast | Actor | UBS Network director | 2 |
 Park Yu-mil | Cast | Actress | UBS Network staff | 1 |
 Baek Suk-kwang | Cast | Na Sung-jin | 2 | |
 Yun Bu-jin | Cast | Actress | Neighbourhood woman | 1 |
 Kim Joon-hyung | Cast | Actor | Sanga University coach | 2 |
 Jeon Jun-woo | Cast | Actor | Restaurant host | 1 |
 Yoo Min-joo | Cast | Actress | Park Hye-jin | 1 |
 Seo Jae-hee | Cast | Actress | Shin Jae-kyung | 16 |
 Song Young-joo | Cast | Actress | Bo-mi's friend | 1 |
 Park Ji-ho | Cast | Actor | UBS Network documentary staff | 2 |
 Kim Jun-ho | Cast | Actor | Jun-ho | 1 |
Cho Min-wook | Cast | Actor | Kwon Dung-uk | 5 |
 Jung Yong-ju | Cast | Actor | Delinquent boy | 2 |
 Jeon Yeong | Cast | Actress | Yogurt lady | 2 |
 Bae Yu-ri | Cast | Actress | Hotel receptionist | 1 |
 Shin Hee-cheol | Cast | Actor | Detective Kim | 1 |
 Hong Eun-jeong | Cast | Actress | Job interviewee | 1 |
 Garrison Farquharson-Keener | Cast | Actor | Alan Smith | 2 |
 Guk Joong-woong | Cast | Actor | Referee | 1 |
| Person | Type | Job | Role(s) | Episodes |
