Southland returns to TNT on January 4.

What can fans expect from the first episode back, which is titled "Let It Snow?" Look for...

... Ben to get hit on during a traffic stop.

... Lydia to clash with her new partner, played by Jenny Gago, over the case of an llegal immigrant.

... Russell to struggle with his new desk job in the department.

... John to try and manage his pain issues.

As for the season as a whole? This preview makes it clear that the keeping and exposing of secrets among various character will play a major role:

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.