We've uncovered a bit of Southland season finale scoop.

On the May 21 episode, titled "Derailed," expect to see cliff-hanger involving Dewey (C. Thomas Howell) and his out-of-control drinking.

Also, Lupe Ontiveros (who played Carlos’ mom on Desperate Housewives) guest stars as a ferocious gang-lord mother, while Officer Sal (Michael McGrady) searches for his missing teenage daughter.

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