| How hard can it be to go back to your old job? Law Yiu Wah (Moses Chan) was a teacher at a dangerous high school before he was forced to resign over a peeping Tom controversy. Wah becomes a police officer but then is asked to go back to his old high school to investigate a triad drug network at the school. |
| Name | Character | Episodes |
|---|---|---|
| Lily Li | 30 | |
| Rainbow Ching | 30 | |
| Moses Chan | Law Yiu-wah | 30 |
| Benjamin Yuen Wai-Ho | 30 | |
| Ron Ng Cheuk-Hai | Ching Man-lik | 30 |
| Henry Yu Yang | 30 | |
| Lee Kwok-Lun | 30 | |
| Linda Chung | Carman Koo Ka-lam | 30 |
| Jason Pai Piao | 30 | |
| Thomas Sin Ho-Ying | 30 | |
| Jonathan Cheung Wing-Hong | 30 | |
| Law Ho-Kai | 30 | |
| Wong Ka-Lok | 30 |