While holidaying in Italy, Angela Marchmont is persuaded to postpone her trip to Venice and go to Stresa instead, to investigate a pair of spiritualists who are suspected of defrauding some of the town's English residents out of their money. But what starts out as a minor matter swiftly becomes more serious when one of the residents in question is found dead in the beautiful gardens of his home, having apparently committed suicide.
Seduced by the heady sights and scents of the Italian Lakes, and distracted by an unexpected encounter with an old adversary who seems bent on provoking her, Angela sets out to find out the truth of the affair and resume her journey to Venice before she forgets herself and loses her head—and her heart.