Kevin Alejandro, <i>Southland</i> Kevin Alejandro, Southland

Southland is strongest when it allows the police officers' work to bleed into their personal lives.

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In Tuesday's episode (10/9c on TNT) that's the case for Detectives Nate Moretta (Kevin Alejandro

) and Sammy Bryant (Shawn Hatosy)."You get to go on a journey with Nate and Sammy and sort of discover who they are," Alejandro tells TVGuide.com "You learn how they deal with life, their personalities and how they grab on to certain things. There's some big stuff that happens. It's one of my favorite episodes."Through the second season, Nate and Sammy have been part of a task force building a case against Trinny Day (Wood Harris), an ex-gang member who claims to have cleaned up his act. The case intensifies when gangsters take aim at a club and kill someone with connections to a cop.But for Sammy and Nate, it's personal. Sammy learns that his wife has been photographing gang members, which he fears could compromise his investigation. Nate's teenaged daughter also runs in circles connected to Trinny.

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"You get to see just how his relationship with his daughter affects him. She's very involved," Alejandro says. "She's involved herself in a part of life that greatly affects his work life. You get to see how that turns out and how Nate reacts to her as his child."But while partners are usually able to lean on one another during trying times, Nate and Sammy are more divided than ever, thanks to Gil Puente (Laz Alonso), the task force leader. Gil and Nate worked together years before, and their history has put a strain on Nate's bond with Sammy."It's hard for us," Alejandro says, "You get to see this sort of friction. They're off balance, and you get to see how off balance they are. But it also all comes back around. Hopefully, they will evolve and get back to normalcy. It tests the strengths of their relationship as partners."Alejandro says the next episode touches on where Nate's true loyalty would lie, if a line were drawn in the sand. He also says the episode makes big strides in closing the case. "You feel in the air that closure is just around the corner," he says.

Will Southland be different on TNT?

Even though Southland's run on TNT is almost up (the cable network is running  the six episodes originally ordered by NBC before the network canceled the show), Alejandro says he hopes a lack of closure for some characters will lead to a renewal for next season.

"I think by the end of the season, all the Southland fans will have had the opportunity to grab onto the characters that they love," Alejandro says. "All the characters have really opened up and blossomed into real people. ... and I hope people will want to grab on and continue to see more of these people's lives.

"I've heard some ideas of where they want to go with the characters, and there is so much more to the story than we're able to share right now," Alejandro says. "There's a tremendous amount underneath all the characters right now that could — and, I think, deserves — to come out."