Natalie Boal is the ex-girlfriend and former patient of Hayden Price.
In reality, Boal was also a scam artist like Price and was running a love con on him. She met him by becoming one of his patients and used her skills to make him fall genuinely in love with her.
Boal utilized her access to Price's files to learn that one of his patients, Sven Vanger, was laundering money for HR through his sports memorabilia store. She was aware that Price had spoofed an email to Vanger, in which he changed an auction lot number from the worthless item Vanger was to buy to a very rare baseball signed by the 1927 Yankees, including Babe Ruth. Vanger ended up winning the ball for $4.4 million, but since he thought it was another worthless prop, he sold it to one of Price's associates referred to as the "Soda Boy" for $5. The boy had made a deal with Price to sell the ball to him for $20, but Boal persuaded him to give Price a fake ball and sell the real one to her for $100.
Price called Boal to confess that he was in fact a criminal and begged her to leave the country with him. At this time, Natalie showed her true colors and informed Price that she had conned him.