Treena Morris has had more experience taking on new identities than most protected witnesses. Treena-aka Trudy Wainright, aka Tenley Bishop, aka Toni Denard, aka Teri Ranzino-is a con artist (even worse than murderers in Mary's opinion). Her particular skill: making men fall so crazy, head-over-heels in love with her that they'll do stupid things, such as hand her a bag full of illegal conflict diamonds and trust that she'll put them in the safe. Her current husband/mark is just that gullible. Unfortunately for her, before she can get away with half the diamonds, the Feds bust her.
On the plus side, she's got more than enough dirt on her diamond-smuggler husband to make a deal. Mary is understandably disgusted when she's told she has to help this woman get a fresh start. She's even angrier when Treena gets engaged to one of the wealthiest men in Albuquerque, allows her engagement photo to be put in the paper (a WITSEC no-no), and refuses to call off the wedding despite Mary's warnings. Treena doesn't endear herself to Mary any further when she introduces Mary to her friends and family as a U.S. Marshal (again, a definite Program Don't) and her maid of honor. Now Mary has to keep Treena safe from angry diamond smugglers and keep Treena's fiancé safe from her-all while wearing a horrid bridesmaid dress.
Meanwhile, Raphael's hitting streak for his Minor League team has earned him an offer from the Florida Marlins. Mary's certainly happy for him but isn't sure how she feels about the fact that he's only got a few days left in town. What she doesn't have mixed feelings about is the offer Raph makes to her via a very odd (and edible) mode of communication: a cupcake. By the time Mary realizes that her first response might not have been her best response, it just may just be too late.