Puppet Master 3 is more serious that its predecessors. It's a prologue to the series, excluding Retro Puppet master. The movie vaguely explains what the puppets were previously without studying each case separately. However, we learn almost everything we could have wanted to know on Blade, who is, in my humble opinion, the most interesting puppet of all.
The historical aspect of the movie is very interesting. I like the Nazi context, an aspect that is usually left out of horror movies. Also, a new puppet is introduced: Six-Shooter.
The incoherence of this series doesn't bother me as much now. We learn at a certain point that every puppet is the reincarnation of a deceased friend of André Toulon. However, the final scene explains the origin of Blade and the logical explanation loses all its sense. Retro Puppet master (the seventh movie in the series) will try to give more in depth explanations but will ruin the pertinence behind the story of the puppets... unless I didn't understand a thing!