The plot centers around a South American warlord who had been deposed by Arnold's platoon and seeks to use Arnold to return to power. In order to get Arnold to play along, he kidnaps his daughter,2 a rookie villain mistake. Arnold then unleashes his fury on all who laid a finger on his daughter. He single-handedly kills an entire compound of armed men.
I wouldn't be a good feminist if I didn't point out that this movie does, unfortunately, rely on the trope of a woman who is basically kidnapped by the hero, is hysterical, but then, for some unknown reason, continues to follow him and seems to fall in love with him. The underlying message is that women shouldn't worry if a guy they've met is controlling and obviously violent. Even though he seems to have no respect for her personal property, the fact that he's doing it "for a good reason" absolves all guilt on his part. While action movies have done a lot to beef up the women in them, they still largely tend to follow this unfortunate path.
1. As mentioned in previous posts, I shall use the common usage of "Arnold" rather than his last name of "Schwarznegger."
2. Played by a very young Alyssa Malano.