Mary's latest witness is a smooth-talking con man, who finds it impossible to leave behind his life of swindling other people even while in the witness protection program. But despite discovering that he has failed to leave his old ways behind, Mary is even more frustrated to learn that his inside connections to a major weapons trafficker make it impossible for the federal government to drop him from WITSEC -- and instead requires that she and Marshall go undercover with him to try to catch the weapons dealer.
After a young Amish woman witnesses another member of her community gunned down by members of a biker gang, she and her husband reluctantly enter WITSEC under Mary's and Marshall's supervision. Soon, however, it begins to appear that her husband likes leaving the restrictions of Amish life behind much better than his wife, making it difficult for her to adjust to the ways of "the English." In the meantime, Mary becomes increasingly puzzled by her sudden weight gain, craving for sweets, and revulsion at the taste of coffee.