In 1858, Charles Darwin thinks about publicly releasing his ideas despite knowing that he would receive backlash from the Christian community. Another major concern for Darwin is that British naturalist Alfred Russel Wallace had the same theory of evolution existing through natural selection and upon the arrival of Wallace's letter to him in June 1858, Darwin becomes worried that he will not be able to publish his own similar theory. While Darwin ponders if he should publish his theory, he discusses the matter with his wife Emma for two weeks while also telling her about the events that led to his theory of natural selection. During this time, their youngest son catches scarlet fever and dies shortly after. The events that Darwin discusses with his wife include his expedition on the HMS "Beagle". Interspersed between their discussions are flashbacks of their family life which includes the time they spent with their children, the experiments that Darwin completed teaching his children, and the death of their 10-year-old daughter Anne. Despite Emma coming to terms with how her husband's research could affect her faith and them both knowing of the backlash that would soon happen, Darwin decides to publish his work under the title of "On the Origin of Species" in 1859.