Mary McCormack Mary McCormack

U.S. marshal Mary Shannon is going to be a mom? That's a scary thought. On this week's episode of In Plain Sight (Sunday, 10/9c, USA), while dealing with a naive Amish witness, the Witness Protection Program agent discovers a recent sexual encounter has left her pregnant. "Her reaction to the news is not good," Mary McCormack says of her grumpy workaholic character. "She never planned to be a mother, so her reaction is shock, denial, avoiding telling her mom and sister — and weighing all her options."

The unexpected story is a result of McCormack's real-life delicate condition. "Running around in tight jeans and little leather jackets, I couldn't hide behind computers like I did with my first pregnancy on The West Wing," says the mother of two girls, who found out she was pregnant the day before she was due on the show's Albuquerque set. Luckily, she adds, "USA copresident Jeff Wachtel thought it being the fourth season, it was a good time for a big change for Mary Shannon."

The actress, whose due date is September 16, is pleased that her character will look "pregnant in a real way. My arms are fat, my boobs are huge, and that's nice for women watching the show." Off screen, one of the first people she told about her condition was Frederick Weller, who plays Shannon's WITSEC partner Marshall Mann, "because we tell each other everything." In fact, when her real life husband Michael Morris was off producing Brothers and Sisters, it was Weller's wife, Ali Marsh (who plays Dr. Shelley Finkle on Sight), who "went with me to birthing classes and for my sonograms."

What can we expect from the hormonal Fed? "She's given up coffee, so she's even grouchier than usual and she's frustrated that her activities on the job are limited," McCormack says, before adding that Shannon could make a pretty good, if unconventional, mom. "She's a quick study and would want her kid to have a better experience than she had. If she raises this child, however, don't expect any cutesy baby talk!" We wouldn't dare.

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