| english title | In the line of duty 4 |
| original title | 皇家師姐 ４ 直擊證人 |
| aka | Survival / Les Dealers de Hong Kong / La Chinoise |
| french title | Le Sens du Devoir 4 |
| year | 1989 |
| country | Hong-Kong |
| director | YUEN Woo-Ping - 袁和平 | |
| actor | Cynthia KHAN - 楊麗青 | Inspectrice Khan |
| Donnie YEN Chi-Tan - 甄子丹 | Inspecteur Yen | |
| Michael WONG Man-Tak - 王敏德 | Agent Wong | |
| WAI Kei-Sun | ||
| CHO Wing | ||
| John SALVITTI | ||
| Michael WOODS | ||
| LIU Kai-Chi - 廖啟智 | ||
| Lisa CHIAO Chiao | ||
| Paul WONG Kwan | ||
| WONG Kwan | ||
| Sunny YUEN Shun-Yi | ||
| YUEN Yat-Choh | ||
| Eddie MAHER | ||
| producer | Stephen SHIN Gei-Yin - 冼杞然 | |
| action director | Paul WONG Kwan | |
| YUEN Yat-Choh | ||
| CHO Wing | ||
| Donnie YEN Chi-Tan - 甄子丹 | ||
| Sunny YUEN Shun-Yi | ||
| YUEN Woo-Ping - 袁和平 | ||
| scriptwriter | Anthony WONG Wing-Fai | |
| CHEUNG Chi-Sing | ||
| artistic director | LEE Chi-Ngai |
| genres | action kung-fu crime |
| duration | 1h31 |
| shooting studio | D&B |
| production studio | D&B |
| distributor | D&B |
| classification | Hong-Kong:  GB:  |
Donnie Yen and Cynthia Khan as two cops from both sides of the Pacific on the trail of a drug trafficking syndicate. Khan and Yen discover to their dismay that the syndicate has more than one insider working in the law enforcement agencies. As they break the rules to save a witness, the two find themselves pursued by American assassins, Hong Kong gangs and the law.
(source: DVD)
