Charles Stewart's (Timothy Earle) brother Rick (Bill Redvers) went missing when both brothers were fighting in the Vietnam War. Charles never could believe his brother actually died then, and he's even less convinced when the Army suddenly sends a letter to his mother telling the family Rick is dead.
Charles scepticism is very correct, too, for Rick has been pressed into the super soldier program of the brothers' old superior Spacek (Bengt Fridh), where he has been turned into a drugged, mind-controlled killer. And one prophetic of modern US military tactics one to boot: in a little real world training exercise, Rick and his super soldier friends not only kill their target, but also a bunch of innocent bystanders (look forward to the bloody death of some kids, blood spatter friends). I'm only surprised the soldiers didn't wait for ambulances to kill the medics too.
It is this horrible mess that brings Charles on the track of the whole program via a camera man who filmed it, a journalist who got the tape, and Spacek's tendency to let his men run around killing people left and right.
Charles's goal is clear: find the location where the soldiers are kept, free his brother, kill Spacek, and don't bother to get Rick psychiatric help and then be surprised when the abused man slits the throat of the rather too friendly neighbour.
I would be more than a little surprised if Roland Emmerich (or one or more of his scriptwriters) had not seen this Swedish ultra low budget production before making their Universal Soldier, though, say what you will about Emmerich, the resulting Hollywood movie is admittedly quite a bit more competently made and not just a rip-off of War Dog.
Of course, Emmerich and co did have the advantage of things like a professional crew and a minor Hollywood budget where War Dog (which I like to imagine as the prequel to War Horse or the third part of the War Bus series, or both) is held together by spit, shoestrings and pure enthusiasm.
Given that fact (and the plot synopsis above), it will come as no surprise to anyone to hear that War Dog is a cheese fest of the first degree full of all the things that make low budget action movies like this - depending on one's tastes - either brilliant entertainment or totally unwatchable. If you're in the market for horrible yet frequently funny dialogue, the slightly chubby guy from next door as an action hero, explosions (alas, no grass or bamboo huts), slow motion, and slow motion explosions, improbable gun sounds, the Swedish countryside standing in for the mid-western USA, a random/awesome/generic synthesizer soundtrack, and all the government conspiracy crap you could ever want, all not really connected by sloppy yet surprisingly creative direction, then you're in for a treat. If not, I don't think you should be reading about a film called War Dog, and even less watch one.