Taking advantage of Paramount's "frozen funds" in Britain, producer Hal Wallis was able to film much of So Evil My Love in London. Based on a novel by Joseph Shearing, whose previous Gothic romances included Moss Rose and Blanche Fury, the film stars Ray Milland in his first (but hardly his last) all-out villainous characterization. Milland is cast as charming scoundrel Mark Bellis, or at least that's what he's calling himself at the moment. Escaping his latest criminal escapade by boat, Bellis falls victim to a malaria epidemic. Nursed back to health by young widow Olivia Harwood (Ann Todd), Bellis repays the favor by pretending to fall in love with her, all the while intending to deplete her of her estate and bank account. Eventually Bellis' evil nature corrupts Olivia as well, prompting her to indulge in blackmail, with her old school friend Susan Courtney (Geraldine Fitzgerald) as the victim. Eventually, Olivia is driven to commit murder, carefully arranging the evidence to convict poor Susan. But when Bellis double-crosses her one time too many, Olivia belatedly does the "right thing," clearing her conscience if not her good name.
by Hal Erickson synopsis