'In Plain Sight' star Mary McCormack on final season: There will be closure for Mary and Marshall fans

Deputy Marshall Mary Shannon (Mary McCormack) is back for a fifth and final season of In Plain Sight tonight on USA, but this time around, things are a little complicated. Well, actually, they’re very complicated by something that’s very little.

At the end of last season, McCormack went into labor after spending much of the season (on screen and off) juggling pregnancy and a demanding job. Her character, however, seemed set on giving the child up for adoption. Tonight, we learn just how that worked out. (Yeah, it didn’t happen.) And now Mary is faced with fresh challenges as a new mom. “I have a newborn — she’s six months today. So I can relate to being tired and trying to do your job well and not being very good at either,” says McCormack. “She’s managing. She’s grouchier than ever, but she’s managing.”

The IPS writers room had to do a bit of managing themselves going into this final season. With only eight episodes to wrap up a laundry list of hanging plots and some uncharted territory to explore, the to-do list seemed ambitious. But McCormack says the advance notice about the show’s conclusion enabled them to craft a proper end to the story. So, yes, Mary and Marshall (Fred Weller) fans, there will be closure.

“You definitely will see it dealt with,” says McCormack of the fan-favorite pairing between Mary and her longtime partner. “I don’t think I should tell which way it will go, but it won’t be ignored. We carry that right through [the end of the series]. It’s in every episode because fans of the show are interested in what that is and what it has the potential to be.” In tonight’s episode, the build up toward the climax of this storyline seemingly begins as viewers see hints of Mary’s jealousy toward Marshall’s girlfriend.

Get more EW: Subscribe to the magazine for only 33¢ an issue!

And these last episodes will also explore Mary’s family a bit more, with the introduction of her absent father in episode 5. “[He's] a big part of her loss and injury and why she is how she is,” says McCormack. “It is the source of her anger, sadness, control issues. It’s all about that guy. It changes everything for her.” Another curve ball? Her character’s sudden romantic entanglement with Cougar Town actor Josh Hopkins. He plays a love interest named Kenny, who Mary meets in a coffee shop. “Everything is changing in her life” says McCormack.

The same can be said for McCormack herself, who after five seasons of helming a stunt-heavy show is entering the world of half-hour comedies with a new pilot from New Adventures of Old Christine creator Kari Lizer. McCormack plays a mom who becomes a stay-at-home mother in a house of teenagers after being fired from the high-pressure corporate job she’d held for years. “She’s a fish out of water in her own home,” McCormack says of the character. But McCormack welcomes the opportunity for change.

“Five years is a long time to play one part…my life is different than when I started,” she says. “But it’s been a really great role, and I don’t think I could have found a better part anywhere.”