“Den Of Thieves” (** out of four) was an overdone, overlong Los Angeles underworld melodrama about a troubled cop (Gerard Butler) and his efforts to stop the state’s most successful bank robbery crew and their leader in particular (Pablo Schreiber) who he develops a vendetta against. For a movie about thievery, this borrows an awful lot from “Heat” but writer-director Christian Gudecast is no Michael Mann and Butler and Schreiber aren’t exactly at the level of Al Pacino and Robert De Niro. Film holds your attention with violence, style, and its gritty action scenes but script is weak and character motivations are murky.