Dolph Lundgren delivers a roundhouse kick to one of the bad guys upon entering a building. The kick connected and knocked out the actor because the actor missed his mark.
Matthias Hues, who played the film's alien bad guy, performed all of his own stunts because there were no doubles who could match his size (6'5").
The project was initially titled "Lethal Contact" (as it was first written in 1984 as a spec script by Jonathan Tydor). The production, filming and international title is "Dark Angel", and was released as such worldwide, before it was changed to "I Come in Peace" for the late U.S. release, because of two other existing movies entitled "The Dark Angel" (from 1925 and 1935).
The contact lenses Matthias Hues wore for his character of the "Bad Alien" made him practically blind. Often the crew members were concerned he would not survive the many explosions and stunts performed in the film.