His first film was Girls Without Tomorrow 1992 (1992) and at the time he was still called by the name Dior Cheng. He changed his name to "Ekin" before his break-out role in the Young and Dangerous series as Chan Ho-nam. The film was first meant to glorify the triad life, but after about the third film, the story focused more on the characters and explored the truth about the Hong Kong triads. It became so popular that it launched Cheng and co-star Jordan Chan to superstar status. And because of its incredible success, it is said to have made many youngsters at that time fond of the triad life, thus making teens throughout Asia join the triads. It also started a trend for triad films around that time and is considered to be a classic. The film led to six sequels, all starring Cheng, and a lucrative working partnership with Director Andrew Lau. Together they went on to make The Storm Riders, which was the highest-grossing Hong Kong movie at the time and the first film to use a truly large number of special effects. They also worked together on The Legend of Speed, a film about a street racer who would follow his father's footsteps of becoming a racing god, A Man Called Hero a movie adaption of the famous comic, about a martial arts master in America The Duel starring Cheng, Andy Lau, and a few other famous stars, and the comedy Women From Mars. In 2001, he acted in a movie titled Born to be King. This is the last instalment of a triad movie series Young & Dangerous.