Overview
Agents are a group of characters in the fictional universe of The Matrix franchise. They are guardians within the computer-generated world of the Matrix, protecting it from anyone or anything (most often Redpills) that could reveal it as a false reality or threaten it in any other way. Agents also hunt down and terminate any rogue programs, such as The Keymaker, which no longer serve a purpose to the overall Machine objective. They are sentient computer programs disguised as human government agents, physically appearing as human but with a tendency to speak and act in highly precise and mechanical ways.
A notable individual Agent is Agent Smith, played by Hugo Weaving. He is introduced alongside his colleagues Agents Jones (Robert Taylor) and Brown (Paul Goddard) in the first The Matrix film in 1999. Other Agent characters have appeared in various media adaptations of the Matrix franchise.
Physical aspects
Agents appear in the guise of human government agents, wearing black-green business suits lined with a gold fabric, white dress shirts, black dress shoes, dark green neckties with a silver bar clip, square sunglasses, and a communication earpiece. These features are copied from the attire for plainclothes agents of the United States Secret Service, as well as those of the Men in Black conspiracy or the stereotypical G-Man/FBI official. All known individual Agents within The Matrix universe appear as Caucasian males. In The Matrix Reloaded, six months after the facts of The Matrix, the Source deployed the upgraded Agents Jackson, Johnson, and Thompson (portrayed by Daniel Bernhardt, David A. Kilde and Matt McColm), designed specifically by the Machines to defeat The One. Unlike the original Agents, they had a change of appearance: their suit jackets were lighter and had more of a grayish-green tone, they were bulkier, wider and taller in appearance. The Upgraded Agents also spoke with a slight, almost unnoticeable reverb effect to their voices, which made them sound intimidating even while discussing mundane matters; unlike the regular Agents who sounded perfectly normal.
Agents are, in fact, highly advanced artificial intelligence entities,
programmed with a number of superhuman abilities. As Agents do not exist in their own bodies as other programs do, being "killed" is a temporary inconvenience.
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