The House on Telegraph Hill (1951)

Victoria has survived Nazi concentration by assuming the identity of one who died there. She arrives in San Francisco to see her "son" just as the boy's great-aunt dies leaving a lot of money to be inherited. Victoria falls in love with the boy's trustee Alan Spender, and they move into the mansion on Telegraph Hill. She then learns that Alan and his lover, the boy's governess Margaret, murdered an aunt and are planning the same for her.