In the movie, Bella is a young woman who behaves in a very childlike way. Bella’s guardian Godwin (played by Willem Dafoe) explains that Bella is actually one of his experiments, and that Bella was originally a pregnant woman who jumped off a bridge, intending to kill herself. Godwin then resurrected her but replaced her brain with that of her unborn baby’s, basically giving an adult woman the brain of a baby. So, as the movie goes on, Bella embarks on a journey of her own and learns more about the world at an extremely rapid pace.