Trivia

Director Benny Chan described the filming process as some of the darkest days of his career, explaining that the baby was a factor beyond his control, and could not work more than eight hours a day. Whenever a scene involving the baby was shot, the crew members had to be silent, communicating in sign language. Benny Chan stated it took time, patience, and money to guide the baby through each shot, and numerous retakes were required due to the baby's constant crying and napping. As a result, production went over budget. Special methods were sometimes used to coax the baby into co-operation. One scene required the baby to suckle Chan's nipple. The baby was initially hesitant, but relented after the crew brushed a large amount of honey onto the nipple.

Jackie Chan suffered minor injuries attempting stunts in this movie, having been kicked in the chest by a stuntman wearing the wrong boots and fallen off a quad bike, while attempting to perform a wheelie.

Over one hundred auditions were held before the suitable baby was found to appear in this movie. Benny Chan chose Matthew Medvedev, a one-year-old infant of Chinese and Colombian descent. Medvedev, known as "Baby Matthew", was literally recruited off the street when an assistant director spotted him with his parents on the MTR. Although his family was simply visiting Hong Kong, they agreed to stay and let Matthew appear in this movie.

Daniel Wu and Nicholas Tse, stars of Historia Policiaca 5: Máxima Traición (2004), make cameo appearances as gay security van drivers during a car chase in this movie.

Jackie Chan and Michael Hui appeared in The Cannonball Run (1981).