Michael Peña and Jake Gyllenhaal in a publicity still of "End of Watch" (2012) directed by David AyerEND OF WATCH hits theaters nationwide on September 28For his upcoming drama "End of Watch," actor Jake Gyllenhaal went to great lengths to believably transform himself into an LAPD uniformed officer. He spent five months in physical and tactical training, he rode along on patrols, and, it should be noted, he shaved his head.How successful was he at turning himself into a cop? So much so that real police officers didn't realize he was an actor and not one of them.In an email interview, the film's writer and director David Ayer (who also wrote "Training Day" and "The Fast and the Furious") explained how it happened. He said that the movie's "found footage" shooting style required the camera crew to stay out of sight while Gyllenhaal and Michael Peña, who plays his partner, performed their scenes. Ayer said, "There were times where Jake and Mike are in uniform in a marked police vehicle," and there were no cameras to indicate a movie was being filmed.Ayer recalled, "Cops in LA will do a hand sign with four fingers to say 'everything's good.' Jake threw a 'Code Four' at some LAPD cops rolling by and they threw a 'Code Four' back. I don't think they had any idea it was Jake Gyllenhaal!" Source: movies.yahoo.com

read more: Jake Gyllenhaal: a realistic portrait of a LAPD officer in "End of Watch"