Impostor's lure
(Book)

"The murder of a federal prosecutor with an art forgery in his hotel room draws FBI agents Emma Sharpe and Colin Donovan and HIT, their small, elite Boston-based team, into a high-stakes hunt for an assassin who has killed before and will kill again. The high-stakes hunt draws on Emma's expertise in art crimes and her past as a novice with a convent specializing in art conservation, on Colin's experience as a deep-cover agent, and on the strengths of their families and friendships as well as their FBI colleagues. The action moves from Boston to small-town Maine and back again in a frenzied hunt to catch a killer."--,(Source of summary not specified).