After the police tell thirteen-year-old Jan that his communist father is wanted for murdering an SA man, the only person willing to befriend him is Max, who is involved with a resistance group.

World-famous geneticist Professor Hülsenbeck (Norbert Christian) is a man of integrity who refuses to mix science and political gain. Because his findings are being used to harm humanity, he imigrates to the United States in 1933 in protest against Nazi racial politics.