When Capt. Sharon Raydor first took over the Major Crimes Division of the LAPD, her detectives were wary of the seemingly by-the-book former head of Internal Affairs who had given their former boss, Deputy Chief Brenda Leigh Johnson, such a hard time.

As Season 2 of TNT’s hit drama “Major Crimes” begins at 8 p.m. Monday, Raydor has won over her team—and mastered the art of gaming the system. But two-time Oscar nominee Mary McDonnell swears her character always had it in her.

“We only saw her in relation to her both having to keep an eye on Brenda and the gang and eventually having to help them not hang themselves,” McDonnell told me recently. “We didn’t know about how she gamed the system in Internal Affairs. … We only saw her in a very narrow world. We’re beginning to see how good she is at gaming.”

The narrow world in which viewers saw Raydor was when she was first introduced in “The Closer,” which starred Kyra Sedgwick as Johnson. Since then, creator James Duff, McDonnell and other “The Closer” cast members have successfully transitioned to “Major Crimes,” which became the No. 1 new drama on cable last year with an average 7 million viewers.

McDonnell, who is no stranger to playing a leader thanks to her role as President Laura Roslin in the sci-fi series “Battlestar Galactica,” said fans can expect more personality clashes in the new season, but not the kind of power struggles that plagued the divison last season.

Viewers will see more of Raydor’s emotional side when a new Deputy District Attorney Ema Rios (Nadine Velazquez) challenges Raydor’s relationship with foster son Rusty (Graham Patrick Martin), as well as how she handles certain cases. And the always surprising captain will get a visit from her not-quite-ex-husband, played by Tom Berenger.

“This is a very eccentric marriage,” McDonnell said, laughing. “She’s still married. They haven’t lived together in ages but there’s no talk of divorce. … One would have assumed when we first met Sharon that everything about her was orthodox. And what I’m finding out is that’s not the case at all. She’s very unorthodox.”

McDonnell talked more about the new season, finding out new things about Raydor and how she feels “Major Crimes” has become it’s own animal.

How excited you are for the new season?
I’m very excited. We’re in the thick of it and I am extremely pleased with the revelations of character, of relationship, of dilemma. I feel like in this ensemble is moving into just a whole new level of work. And we do have a new show on our hands. And what’s beautiful about it is that there was never a moment where we had to fully abandon the old, which we haven’t. But the organic growing into a new form has been such a delight to witness. So we’re all feeling very excited. It feels very fresh and I love that.

How has the show evolved?
Well, it’s changed in many ways. One is that if we just look at the reason that Sharon Raydor by story was put in the position that she’s in now, which is running the Major Crimes Division, has to do with some of her gifts which has to do with her ability to comprehend the overall—the politics of the state, the politics of the justice system. And all of those things are influencing the way justice can be disseminated. And she has a gift for the overview.

As opposed to another detective who is like a bloodhound who might have a gift for getting caught on one idea and following that line all the way through. Sharon has a gift for keeping the overview. So they put her in that position because the state of California can’t afford justice as it has been acted out prior to now. We can’t afford the convictions anymore. We have to figure out a different way to solution because the cost of keeping a convicted death row criminal waiting for trial and the cost of having appeals is so overwhelming and the state simply doesn’t have the money.

So what’s fascinating is that all of these politics and this situation is part of why she’s there. And finding out in fact that she’s actually really good at reformation and she’s really good at figuring out how to change the way things run. And one of the things that I’m discovering that I really love about her is that she’s a great leader in that she absolutely wants to draw out the very best of those around her. And so that has shifted them a little bit away from some of the power struggles that were running Season 1. It doesn’t mean to say there won’t still be power struggles in personality, but I think we’re in a new world in terms of the way we’re going about things as a team. And I love how she’s influenced that.

Something that I loved is that it seems like from when we first met her she’s sort of learned how to game the system herself now, hasn’t she?
She definitely has. Well, here’s the thing that we never knew about her because we only saw her within a certain functionality on “The Closer.” … But at any rate I do completely agree with you in that we’re beginning to see how good she is at gaming. And we’re beginning to see what I’m experiencing in her—let’s perhaps say there was a latent detective in her. She had to use her detective sense in Internal Affairs because she got to police the police. But there’s a different kind of thing that’s being asked of her now as a cop. The direct relationship to the actual murder and having to send her squad into dangerous territory—all these things are deepening her and we’re finding out more about what she’s capable of.

So you feel like she’s definitely even grown from when you first started playing her?
Oh, without a doubt. Oh my gosh, yes. Yeah.

Is she becoming more interesting for you?
Oh, totally. Totally. And it isn’t that I wasn’t interested in her before; I was fascinated. I loved her from the very beginning. But there was just a very specific world that she existed in as a functionary. And now I’m finding out things about her every episode that I didn’t know. And I love it.

Is that the beauty of series TV for you?
It is the beauty of series TV for me. I love series TV because you’re standing at the precipice of something new every week if you’re lucky, if you got good writers. If you don’t have good writers you’re really in trouble and I guess you just celebrate your paycheck. Do you know what I mean? But in this case great writing. Every week I’m finding out something more about her. And I come home and I go, “I cannot believe how lucky I am to have this job.” That’s how I feel.

Like for example this season this discovery of what the state of her marriage, and Tom Berenger and I sort of exploring that together, has been an absolute blast.

Tell me about Rusty and Nadine Velasquez’s character. It looks like Nadine’s character is going to become a sparring partner for Sharon?
Well, there are some concerns, I’ll put it that way. On the one hand I think Nadine’s character is the perfect kind character that Sharon Raydor by her nature would promote. She’s a big feminist, Sharon Raydor, on some level. So the idea of a young, bright, up-and-coming D.A. that she can help would be exciting. And she would definitely support her.

This particular woman is presenting some dilemmas stylistically. And because it has to do with Rusty and Sharon’s feelings about Rusty, that taps into the maternal archetype; things can get very complicated. There’s the cop, there’s the mother, there’s the head of major crimes, there’s the person who interacts beautifully with the D.A.’s office.

She has a really strong political overview and she knows how to operate on those levels. That’s why they put her in this position because they knew they had to deal with the D.A. and she’s good at that. She understands lawyers. She understands all of that. She’s really good at it. But this particular D.D.A. is presenting her with some problems.

And will that continue throughout the season?
Well, it certainly has shown up in a few episodes.

The film producer character in the first episode is so obnoxious. How accurate in your experience is that portrayal?
Well, this is what I’ll say about that. He is such a marvelous actor and one of the things I love about this show is that it has some flexibility in its boundaries. So stylistically the show can sometimes go way over here and then come back. And he was so funny and so outrageous. But I have to say that if you really just looked at what he said, it’s not surprising. There is that archetype in Hollywood for sure. I can’t tell you that I’ve worked with many producers like that, but I met them. [Laughs.]