911: Officer Down (2018) online

While taping an episode of a popular police reality TV show, "L.A. Beat", a cop and a film crew are taken hostage by a vigilante hell-bent on revenge. Disguised as a police officer, the hijacker cruises the streets and alleys of the Los Angeles underbelly, delivering his own twisted style of justice. The film crew follows and records the action, as the vigilante hunts down drug dealers, vandals, pimps and more