Karen Sisco - Season 1 Episode 3 The One that Got Away
Overview: When a suave con artist who bilks women out of their fortunes manages to slip away from Karen the minute he's off the plane, she's humiliated but determined to bring him in, despite the fact the FBI has ordered her off the case. Meanwhile, a former mob accountant suddenly returns from hiding in the witness protection program, putting his — and Karen's — life in jeopardy; and Marshall is unhappy to find that Karen's old boyfriend, a married FBI agent, is back on the scene.