While mostly fast-paced and watchable, "Law of the Wolf" (also called "Law of the Wild") is too far-fetched and melodramatic to be taken very seriously. The plot does work fairly well as light entertainment, despite a complete lack of believability.
When Carl Pearson (Dennis Moore) is unjustly convicted of killing his brother, he breaks out of prison with the help of another convict to try to clear his name and also to recover some valuable airplane plans that his brother left behind. He is pursued both by the police and by the real killer, while his fellow escapee tries to turn the situation to his own advantage. Quite a bit happens from there, most of it dependent on coincidence, on weird decisions by the characters, and on improbable events. Whenever these cannot take care of everything, Rin Tin Tin Jr. is on hand to fix things up with his amazing insight into human intentions.
It moves fast enough to keep your attention most of the time, but it is all too far-fetched to be anything more than very light entertainment.