Charles Darwin (Paul Bettany) has an especially close relationship with his daughter Annie (Martha West), who takes to his theory of evolution and adores his true stories about animals. Annie dies, and Darwin is devastated. Annie’s death is a key source of tension between Darwin and his wife Emma (Jennifer Connelly). Their relationship is also strained by Darwin’s theory of evolution – he has been developing and writing his theory of natural selection, but she finds it heretical. He is beaten to the punch by another scientist, but Darwin’s own research is much more detailed and comprehensive. Torn, he ultimately gets Emma to decide, and she pushes forward with the decision to publish.