If any of you reading this (both of you?) like Stranger Things, this movie was almost certainly a huge influence on it.
This movie means something to me for a couple of reasons. First, it is based on the first Dean Koontz novel I ever read. Second, and more important, the style of story it tells became a template I really enjoy. One of my favorite comics of all time, Suicide Squad (don't judge it by the movie) used to be really good at the same story style. That is to say, you get a primary antagonist and a secondary antagonist (who may be at odds with the primary) and both are after the protagonist on totally separate tracks. In the end, all of them come together and the odds against the protagonist seem insurmountable unless one bad guy takes out the other first.
To make this more concrete, this movie is about a government experiment where they have designed a monster killing machine and a dog that is psychically linked to the monster. The idea is that the dog goes in and finds a target, the monster comes in and kills the target. Corey Haim stars as the boy who finds the escaped dog and adopts him as his own. Not only is the monster on the trail of the dog, a government assassin is on the trail of the boy. Both the monster and the assassin leave a ton of bodies in their wake as they close in on Haim from different directions. The climax is pretty fun.
I don't know where you can currently find this movie but it is an afternoon killer for sure. It might not be the best acted or directed, but I have a soft spot in my heart for it.