In Hong Kong during the year 1966, business partners Paul Wagner and Nigel Griffith open the Victoria Harbour Tunnel.
Frank tells them they are identical twin brothers and they need to join together to take down Griffith and get their part of the royalties from the tunnel, but Chad and Alex initially do not get along with each other.
Alex takes them out on his boat to sell smuggled Mercedes and cigarettes to some Chinese buyers, but the Hong Kong Police arrive and Chad dumps the cars to escape the cops faster.
Back in Hong Kong, some thugs kidnap and beat up Chad (mistaking him for Alex) when he refuses to work for their leader, Raymond Zhang.
Unable to find Alex and Frank who are out gathering firewood, Chad takes the boat to rescue Danielle by himself.
[4] Wanting to breakaway from the martial arts movie genre he had become so popularly known for, he hoped playing the dual role of Chad/Alex would change his image and help him do just that.
[6] Seeing Jeremy Irons portray a dual role in Dead Ringers allegedly influenced Van Damme's decision.
[7] Lettich later recalled the concept of Van Damme playing twins "was so successful that other producers wanted him to repeat it."
(Timecop, Maximum Risk, Replicant) "Even though it meant a lot more work for Jean-Claude, he enjoyed the challenge of playing two distinctly different characters, showcasing a dark and a more light-hearted side in the same movie.
Whilst adding that this "probably won't deter fans," Hicks noted "more gunplay here than in most Van Damme efforts, which may or may not be an improvement."
"Van Damme's idea of a love scene is a soft-lens, soft-core moment as he and newcomer Alonna Shaw roll around nude in a paranoid fantasy sequence.
"[6] Caryn James, of The New York Times , said: "there is plenty of gunfire and karate kicks and explosives set off by remote control.
"[12] Renowned critic Roger Ebert awarded the film two stars, saying: "it has a budget and production values of a lesser James Bond movie."
[This] will hurt their careers in the long run, since martial arts movies are limited by their formulas, and the heroes are supplied with almost ritualistic plot patterns."
"[13] Despite calling the plot "elementary but serviceable", Kevin Thomas, of the Los Angeles Times, gave a positive review, saying: "[Double Impact] offers two Jean-Claude Van Dammes for the price of one, and for fans of the Belgian-born martial arts star, it delivers the goods.
Furthermore, "the studio had to be included as a co-partner with any producing entity", which allegedly made the "process even more difficult and complicated" given MGM's apparent unwillingness to financially back the sequel.
Lettich reaffirmed the cancellation and told fans during the Q&A that "perhaps the biggest reason [a sequel] didn't happen was in fact due to the [original] film's success.