In Victorian London, medical student Max McCandles becomes an assistant to eccentric surgeon Godwin Baxter. He meets and falls in love with Godwin’s ward, a childlike young woman named Bella. Godwin reveals that the woman, who was pregnant, died by suicide after leaping off a bridge. He resurrected Bella by replacing at least parts of her brain with that of an infant’s, which results in Bella waking and having to relearn a great deal of motor functions as well as social skills. She shows no memory of her past life.With Godwin’s permission, Max asks for Bella’s hand in marriage. Bella accepts, but as her intelligence rapidly develops, she begins to crave autonomy and runs off with lawyer Duncan Wedderburn to have an explicit affair. Deciding to let her go, Godwin starts a new experiment with a young woman named Felicity, who matures much more slowly than Bella.Bella and Duncan embark on a grand journey, starting in Lisbon, where the two engage in frequent sex, in addition to other forms of hedonism. She becomes difficult for him to control, so he smuggles her onto a cruise ship for a “change of scenery”.On the ship, she befriends fellow passengers Martha and Harry, who open her mind to philosophy. Initially attracted to Bella’s childlike naivete, Duncan attempts to stunt her growth to no avail. He becomes increasingly exasperated and begins to indulge in drinking and gambling.During a stop at Alexandria, Bella is distraught after witnessing the miserable poverty of the locals and donates Duncan’s winnings, which are in turn stolen by the crew. Unable to afford the rest of the trip, the two are kicked off the ship at Marseille, after which they make their way to Paris.Having run out of funds, Bella begins working at a brothel, further enraging Duncan and resulting in his mental breakdown, finally leading her to abandon him. At the brothel, she comes under the tutelage of Madame Swiney and befriends fellow prostitute Toinette, with whom she begins a relationship and who introduces her to socialism.A terminally ill Godwin asks Max to bring Bella to him. Max locates her after tracking down Duncan, who has been institutionalized after his breakdown. Returning to London, Bella reconciles with Godwin and renews her plans to marry Max. The two are interrupted by Duncan and General Alfie Blessington on their wedding day.Alfie, addressing Bella as Victoria, reveals that they were married before her disappearance and that he has come to reclaim her. She abandons Max to learn of her past life but quickly discovers Alfie’s violent and sadistic nature, and realizes that she had committed suicide to escape their abusive relationship.Alfie confines Bella to his mansion and threatens her at gunpoint to submit to genital mutilation, demanding she drink a chloroform-laced cocktail to sedate her for the procedure. She tosses the cocktail in his face, causing Alfie to shoot himself in the foot before passing out.Godwin dies peacefully with Bella and Max at his side. Bella decides to carry on Godwin’s work with the help of Max and Toinette, while Felicity’s intelligence steadily progresses.
