The title, The Serpent's Egg, had me wondering for a moment until I realized that it did not refer to the the Doctor and his bizarre experiments nor to Abel and his misery, but to the encapsulated Germany of the 1920s and the environment that led to Hitler's ascent in the 1930s. That is, Germany being the 'egg', Hitler and the Nazis as the 'Serpent', and the environment as the embryo of the egg.
In many ways, this is a cynical film, in that it attempts to show that degradation, fear and loss of life and livelihood is sometimes stronger than humanity and even love. Isn't this true about Germany in the 1920s, and other nations at other times as well? We only have to look at ourselves after the attacks of 9/11 to see a time when fear overcame reason. Fear allowed us to meekly accept the chipping away of our own civil rights and privacy, and also government sponsored torture.
It also gives us a glimpse at one of Hitler's truisms, which is that if he could have a person at age 7, then that person would be a Nazi for life. The experimenting Doctor re-states this in his observations that the sons and daughters of the defeated German populace will be the ones who create the new German society, of which he already is a part with his inhumane human experiments.
Of course, all this is done with hindsight, so how can it be wrong? It can't, but then it's still a good review of a period in Germany that many Americans know nothing about, and should learn if they want the answers to the question of how Naziism came to be. It wasn't just some sort of aberration never seen in history before nor repeated.