Jane Finn

In the novel The Secret Adversary, Jane Finn is a young American woman. She left the United States onboard RMS Lusitania, to work as a nurse in Europe during the Great War. She survived the sinking of the ship, and carried papers from a man named Danvers, with her.

Jane speaks French fluently. She later worked as a maid under the alias Annette.

Jane is the daughter of Amos Finn and Jane Hersheimmer, and the cousin of Julius Hersheimmer.

Jane's hair is described as being a "full rich brown, with sudden glints of gold in it as though there were imprisoned sunbeams struggling in its depths". There is a "wild-rose quality" about her face, and her eyes are a "golden hazel". When Tommy sees her, he decides that she is one of the most beautiful girls he has ever seen.

After surviving the sinking of the Lusitania, Jane is abducted by members of Kramenin's gang, and is held captive. To avoid being tortured for information about the papers that Danvers had been carrying, she pretends to have lost her memory, and speaks French to her captors. She is held at a house in Soho, and is later sent to a sanatorium in Bournemouth. During this time, the gang represents her as Janet Vandemeyer, a niece of Mrs Vandemeyer.

Jane spends so much time playing the part of Janet Vandemeyer that her nerves begin to play tricks on her, and she sinks into a stupor for a few months. The gang attempts to test whether her memory loss is real, but she is able to continue pretending. This is made easier by the fact that she had not thought of herself as Jane Finn for a long time.

One night, Jane is taken away from Bournemouth at a moment's notice. She is taken back to London, to the house in Soho, and is sent to wait on Tommy. She later helps Tommy escape from the house, but is caught by the gang before she can take the papers from their hiding place, and escape as well.

Jane is later held by the gang at a house called Astley Priors, in Gatehouse, Kent. She eventually escapes when Julius Hersheimmer comes to rescue her. Jane is then taken by Tuppence to Sir James Peel Edgerton, and tells her story, revealing where the papers are hidden.

Jane goes with Sir James and Tuppence to retrieve the papers. She is present when Mr Brown attempts to steal the papers, and is apprehended.

At the end of the novel, Julius hosts a supper party at the Savoy, where Jane is given the place of honour.

After the supper party, Julius asks Jane to marry him, saying that he does not expect her to love him at once, but wants the right to take care of her. Jane agrees to marry him, saying that she already loves him.

Trivia
It is believed that Christie took inspiration from the name Jane Fish, which she casually heard in a conversation.