Previously in Valentin & The Widow:

It is 1924. Eleanora Rosewood and her valet Sacha Valentin are in Paris, where the Baron von Peller und Karne has tested an Edgar Rosewood weapon that kills with sound. The pair have come to an Olympic art gala to prevent the machine being used to assassinate the President of France. The Baron in turn may be murdered by his mistress Adeline or her lover Jude. Sacha has run into his old foe Sebastien Van Sant, while Eleanora finds herself at knifepoint. Our story concludes.