Gang-cheol is a legendary street fighter in Busan who cleaned up his act to care for his sick mother. Knowing he's desperate for money for his mother's operation, Sang-gon proposes that Gang-cheol works for him.
Unfortunately the movie Tough as Iron is not yet available on Disney Plus.
| Visual Effects | Jung Do-ahn | Special Effects Supervisor |
| Sound | Cho Young-wuk | Music |
| Camera | Yoo Il-seung | Camera Operator |
| Directing | Ahn Kwon-tae | Director |
| Art | Lee Gi-seok | Set Decoration |
| Crew | Lim Wang-sub | Stunts |
| Crew | Lim Seung-mook | Stunts |
| Visual Effects | Yuk Gwan-woo | Visual Effects |
| Production | Lee Min-ho | Producer |
| Sound | Kim Ji-hwan | Production Sound Mixer |
| Camera | Lee Hyung-deok | Director of Photography |
| Writing | Ahn Kwon-tae | Writer |
| Production | Han Sang-hyun | Line Producer |
| Production | Song Jung-min | Production Supervisor |
| Editing | Kim Sun-min | Editor |
| Editing | Kim Mi-young | Editor |
| Lighting | Park Cheong-woo | Lighting Director |
| Costume & Make-Up | An Ji-hyeon | Costume Design |
| Crew | Park Young-sik | Martial Arts Choreographer |
| Costume & Make-Up | Choi Min-seon | Makeup & Hair |
| Art | Kim Soo-gyeong | Art Direction |
