Benjamin McKenzie and John Cudlitz Benjamin McKenzie and John Cudlitz

It's odd to think that the cast of a show entering its third season has never shot more than six episodes at a time, but that's the case for TNT's Southland.

The gritty police drama debuted as a midseason replacement on NBC in 2009 and earned a 13-episode renewal for Season 2. Then, NBC canceled the show before it even premiered, allowing TNT to buy and air the six episodes NBC had in the can in early 2010.

Check out photos of the Southland cast

So when TNT ordered a 10-episode third season, which begins Tuesday at 10/9c, the cast and crew were equally excited and cynical. "Well, the joke on set is on Episode 7 everyone's going to be walking around not knowing what they're doing," Benjamin McKenzie tells with a laugh. "Needless to say the spirit is very good. Morale is very high on-set. We're having a blast knowing we will shoot 10 episodes and they will air."

The real difference, executive producer Christopher Chulack says, is the opportunity to finally craft meaty, uninterrupted arcs for the show's characters. "That's a big help to be able to sit there and know where the end is, at least for this particular season, and dole out the weight of the stories for the various characters," he says. "[We] actually talked about what's the beginning, middle and end of this emotional arc for this particular character and where do we want the relationships of the partners to go and how do they evolve? ... It's a little more refined in the short strokes of the character, and I think that's the hallmark of the show."

At the heart of the series is McKenzie's rookie cop, Ben Sherman, who this season is reaching the end of his probationary period with his painkiller-addicted training officer John Cooper (Michael Cudlitz). And as Ben inches closer to no longer being a trainee, he'll become more vocal about John's continued addiction and back problems.

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"Ben finally has to be the one to tell John some hard truths," McKenzie says. "They are deep friends and partners, but they also have huge conflicts where things are often left unsaid. But they won't be at the end of the season. They will all come out."

But Ben will also battle his own demons as he is forced to face the man who raped his mother when he was a little boy. "It gives you a window into Ben's mentality, the whole reason he became a cop — the reason he has this certain cool on the surface but anger boiling up underneath," McKenzie says. "This uncontrollable rage has to come from somewhere deep down inside. The episode dealing with his mother's rapist gets to the heart of that. We see him get new information that changes the entire way he's thought of himself and perhaps the rest of the world."

Also getting her worldview shaken up this season is Detective Lydia Adams (Regina King), who after riding with a revolving door of partners last season has settled in with loose cannon Josie Ochoa (new cast member Jenny Gago).

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"Lydia's character is a really good cop. She's an 'A' student, she loves being a cop and she's got a partner who has a very specific spin on the way she wants to do her work and how she approaches the job," Chulack says. "[Josie's] psyche of the cop is much different than Lydia's, and for Lydia ... there will come a point in the season where, as much as she loves the department and as much as she loves being a cop, she's going to have to question if this is the right job for her. It's a profound season for this character."

Unlike Lydia, Detective Sammy Bryant (Shawn Hatosy) will lean on his gangs unit partner (Kevin Alejandro) more than ever this season, especially after Sammy's wife (Emily Bergl) drops some life-altering news in the premiere.

"Sammy and his relationship with Nate is an interesting event this year," Chulack says. "You're going to see the domestic life and how they live. In the first four or five episodes, there is a really thick story between these two partners who are very close friends. But events happen that change the course of that and affect another character through to the end of the series. The ripple effect is that great."

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But when will that series end come? Southland's history as a little engine that could has inspired a solid network of fans, but the show's ratings are far less than those of TNT hits The Closer and Rizzoli & Isles. (Season 2's finale drew around 2 million viewers.)

For his part, Chulack didn't approach this season as a farewell.

"We're just telling the stories that interest us, we're not trying to build up to any kind of crescendo," he says. "You do have a finite number and we know certain stories will end there, so we'll lay it out to the end. It's like writing a book: You don't if there will be a sequel, so you try to make it the best book you can. That's what we've tried to do here. We know what we have and the tools we have to make it, and we're going to do our best to force them to bring us back another year."