The Murmuring Portrait

Kay tries to thwart the evil plans of a weird gypsy. 
This teen mystery follows 16-year-old sleuth Kay Tracey as she uncovers a mystery involving a vanishing portrait of a gypsy, a missing heir, a stolen treasure, and a criminal gang.
Kay investigates a mysterious portrait that disappears and reappears in the Moleson Mansion.
She must identify a sinister person who poses for the portrait and stop a gang of thieves from finding a hidden treasure.