Southland (2009)

Lydia and Josie are assigned to assist Sammy and Nate with a series of gang murders. John discovers he can't stand the "new and improved" Dewey, fresh from rehab, when he's forced to ride with him in order to evaluate whether Dewey is competent to return to duty. Ben must then ride with Chickie, who drives him nuts with her very personal questions about his private life and his new relationship with the "cop groupie" he's been seeing.