Treacherous - On the Run International Mysteries, #6

A mysterious package, a rumor about a missing painting, and a dangerous game of hide and seek. Zoe loves working as a consultant for a company that specializes in the recovery of stolen art. Her only complaint is that the jobs are few and far between, so when she meets an eccentric collector who is on the hunt for a painting of a blue butterfly that might-or might not-exist, she jumps at the chance to look for it.
She comes across shady dealers and a confusion of clues as her search for the elusive painting takes her from tropical destinations to the cobblestone streets of Madrid. Treacherous is the sixth installment of the lighthearted On The Run series from USA Today best-selling author Sara Rosett, which features globetrotting art heists and international intrigue.