The Courbet Connection. Genevieve Lenard, #5

Forged masterpieces. Kidnapped students. The dark net. Nonverbal communications expert Doctor Genevieve Lenard's search for an international assassin is rudely interrupted by an autistic teenager who claims that forged masterpieces are being sold on the dark net--a secret internet few know exists. The resulting probe uncovers an underground marketplace offering much more sinister products and services.
Including murder. An official investigation into one of her team members and the discovery of dozens of missing students across Europe adds immense pressure on Genevieve to find out if one person is masterminding these seemingly unrelated cases. What starts out as a search for illegal art sales soon turns into a desperate hunt for clues to uncover the conspiracy to destroy her team member and murder more students.
Timing becomes even more crucial when someone close to her disappears and the assassin she's been looking for is the key to preventing another senseless death.