|“||You are man, he is not man. For you he waits, for you.||„|
|~ Nihilanth about G-Man|
|“||Wake up, Mr. Freeman! Wake up and... smell the ashes...||„|
|~ G-Man sends Freeman on his way to City 17|
During gameplay, G-Man often makes appearances in areas that are out of the player's reach, only confronting the player directly at the end of the game where he has taken away access to their weapons. In-between Half Life and Half Life 2, he seems to put Gordon Freeman in stasis until the Earth has been successfully taken over by the Combine.
G-man is seen throughout the game either watching the player, or tending to another task such as talking to other characters or simply walking through the area. His appearance is that of a business man always wearing a blue suit, tie, and carrying his signature briefcase which upon close observation contains a handgun and photo. Other distinct features being his rough sandy face, flat hair cut and widows peak, and his abnormally light blue eyes. However his most distinct feature is his calm raspy voice, often slurring, pausing between words, and stretching syllables in a way that makes his voice more distinct than others.
This all falls together with his uptight look, he constantly maintains his appearance as he is commonly seen straightening his tie or wiping dirt off his coat, this mixed with his twisted ideals makes him a perfect villain, giving him a calm trust-able facade over a cold monstrous personality.
As G-mans name implies he acts exactly as an agent of the FBI, with his calm clever personality, and his concerns in taking care of the Black Mesa incident in a professional and clean way, leaving Gordon Freeman and Adrian Shephard to do that for him. G-man does not appear to work alone, rather he works for his "employers" as he calls them, saying that he is simply doing what he's told. G-man's job in the incident seems to be simply setting up the dominoes and knocking the first one down, leaving the reaction to occur as he intended in an ultimate effort not to elevate the situation, but to end it.
However he does not seem to be out to stop the problem but to stop it and silence it, leading him to nuke the entire facility and discard of all witnesses except for those he finds useful later on. Though he has a human appearance he is anything but, G-man possesses many supernatural powers such as teleportation, inter-dimensional travel, and even the ability to stop time, also he speaks in a way that seems like he's struggling to pronounce some words, and above all he is completely invulnerable.
Gordon Freeman is a scientist in the Anomalous Materials Labs of the Black Mesa Research Facility where the entire incident begins. G-man is very interested in Gordon, seeing him as a perfect employee due to his persistence and skills which ultimately lead him to stop the invasion and save the world. G-man is seen constantly watching Gordon from a distance even before the incident occurs, he is finally confronted at the end of the game explaining that his "employers" agree with him that Gordon has limitless potential. Though G-man's conversational skills are calm and professional, his negotiation skills are designed to get what he wants. When he confronts Gordon at the end he offers him a job working for him and leads him through a portal which then takes off in Half life 2, but if refused he will teleport him back to the alien homeworld in front of an army of alien grunts leaving him to be massacred by what he addresses as "survivors of your personal holocaust."
Adrian Shephard is a military operative of the Hazardous Environment Combat Unit that infiltrates the facility to combat the alien forces, and Black Mesa personnel. Shephard enters the military academy to become a simple soldier but is strangely bumped up to special training for the HECU. G-man can be seen standing in a window looking down at Shephard in the camp, emphasizing that G-man bumped him up intentionally. Shephard is deployed soon after to combat the incident where he loses most of his squad, and is forced to retreat with the rest of the soldiers, only to be stopped by G-man, denying him escape and forcing him to delve deeper into the facility. Shephard then goes on to deactivate a nuclear warhead placed by Black Op soldiers and destroy the Gene Worm, a large powerful alien coming through a portal in the basement that all the other soldiers failed to destroy. Upon the Gene worm's death Shephard wakes up inside a V-22 Osprey like the one he came to Black Mesa in, except with G-man inside. G-man then informs Shephard that he has done good in his mission and that he has ultimately ended the second invasion.
However as it turns out G-man re-activated the warhead, destroying Black Mesa with an explosion big enough to be seen from the Osprey. He then informs Shephard that there is still the matter of witnesses, which leads him to abandon Shephard in the Osprey which he has teleported to an alternate dimension, leaving him in what G-man sees as "A state where you can do no harm, and no harm can come to you."
G-man played a major role in the Black Mesa incident, being the one who started and ended it. It's revealed by Eli Vance (another one of his employees) that he was the one who supplied Black Mesa with the Xen crystal that caused the accident, and he also re-activated the nuclear warhead that completely destroyed the facility. G-man's motive for causing the incident is clearly an order by his "employers" due to Black Mesa being as G-man tells Shephard "one of the biggest embarrassments". As it is revealed in the game the Black Mesa scientists were constantly traveling back and forth from their dimension to the aliens and bringing back specimens for study, due to the fact that this was entirely dangerous to do, in threat of causing inter-dimensional rifts, or revealing this to the public, it was decided to silence the entire operation before anything could happen.
Though the invasion did what it was supposed to in destroying the facility, and the nuke wiped out the aliens, the rift that was letting the aliens in remained open, leading him to get Gordon and Shephard to close the rifts for him, leaving him to destroy the remaining aliens and people with the nuke, thereby silencing the entire dilemma.
- Originally when Half-Life came out it was thought that G-Man was the often mentioned administrator. This was due to the fact that G-Man stood out and had the appearance of someone in that role, along with the fact that he had the black mesa logo on his briefcase. Many Half-Life mods at the time would assume G-Man was the administrator of Black Mesa, and place him in an antagonistic role, and even online guides would refer to him as 'administrator'. It wasn't until Half-Life 2's release when the administrator was revealed to be Wallace Breen, a completely separate character.
- Half-Life: Blue Shift, Half-Life 2: Episode One and Half-Life 2: Episode Two are the only games in the series that don't end with G-Man putting the player into stasis. Also Blue Shift and Episode One are the only games in which G-Man doesn't oversee the player's actions during the course of the game.
- However it is possible he was somehow overseeing Barney Calhoun's journey in Blue Shift, as the ending of the game gives Barney's status as "Out of Range" (as he managed to escape Black Mesa).
- His ability to disappear and his strange mysterious behavior has often been parodied in Half-Life related media, most notably the Half-Life 2 web-comic Concerned: The Half-Life and Death of Gordon Frohman. A disavowed and hard to find web-comic Catching the G-Man (which could of been found on the Concerned forums) dealt with a main character whose life goal was to try and catch G-Man, but always ended up failing.
- "The right man in the wrong place can make all the difference in the world."
- "Wake up, Mr. Freeman...Wake up, and smell the ashes."
- "Prepare for unforeseen consequences."
- "Time, Dr. Freeman?... Is it really that time again?"
- "You've proved yourself a decisive man so I don't expect you'll have any trouble deciding what to do."
- "Rise and sine Mr. Freeman... Rise and shine..."
- "Time to choose... It's time to choose..."