Barney Calhoun

Barney Calhoun is a main character of the Half-Life franchise.  He shows up in nearly all the Half-Life related games.  His voice acting in all games has been done by Michael Shapiro. 

Barney Calhoun in Half-Life

Barney Calhoun is first seen in Half-Life on the very first level of the game.  Barney Calhoun is the security guard seen banging on the door as the player passes by on the tram.  Many other identical guards show up throughout Half-Life, but this one is the real Barney Calhoun as seen in Half-Life: Blue Shift, when the player reenacts this event from Barney's perspective. The real Barney Calhoun is not seen again in Half-Life, but he does end up seeing Gordon a few times.

About that Beer he Owes you.

If the player repeatedly interacts with the guard after he gets off the train, he will say "Hey, catch me later, I'll buy you a beer." As stated above, this is not Barney Calhoun that says the line however, so when Barney Calhoun mentions the beer later in Half-Life 2 we must assume that it's either a plot hole, an inside joke (referencing the dozens of "Barneys" encountered in the original games), or a case of the real Barney Calhoun also owing Gordon Freeman a beer for some other reason.

Barney Calhoun in Half-Life: Blue Shift

Barney Calhoun is the main character in Half-Life: Blue Shift.  The game focuses on Barney's escape from Black Mesa.  Barney wanders alien-infested hallways and later rescues scientists and together the group of them escape Black Mesa through a teleporter.

Character Sightings

Throughout Blue Shift, Barney is able to catch glimpses of Gordon Freeman and a few other Half-Life characters.

• Gordon Freeman is sighted just after getting off the tram at the beginning of the game.
• Gordon is later seen through a security camera walking down a hallway in Anomalous Materials. (optional)
• Gina Cross is seen through a security camera pushing the Xen crystal sample down a hallway. (optional)
• Gordon is seen unconscious at the end of the game, being carried by HECU troopers.

• The G-Man is seen a few times during the game.

Barney and the G-Man

G-Man is seen during Blue Shift, and may possibly have helped Barney survive during the game.  The G-Man does not "hire" Barney at the end of the game like he does Gordon Freeman, and he does not detain him like he does Adrian Shephard.
 

Barney Calhoun in Half-Life 2

Years after the Black Mesa incident, during the Combine occupation of Earth, Barney has become an important figure in the underground Lambda Resistance in Half-Life 2 .  It is unknown how Barney ended up in City 17 along with Dr. Isaac Kleiner and Dr. Eli Vance.  Barney works undercover as part of Civil Protection.  When he sees Gordon come in on the train he saves him from being sent to the infamous Nova Prospekt detainment center. Barney sends Gordon on his way to Dr. Kleiner's lab.  Towards the end of the game, Barney fights alongside Gordon in the rebellion.

Barney Calhoun in Half-Life 2: Episode One

Barney helps Gordon escort civilians through the train station to the trains waiting to take them out of City 17.  Barney is last seen leaving the city by train while Gordon and Alyx make their way to a second train.

Barney Calhoun in Half-Life 2: Episode Two

Barney does not show up in Episode Two at all.  It's very strange that he is missing and it is not certain if any official statement has been given as to why.  A quote by Gabe Newell humorously suggests that Barney was the small lawn gnome found at the beginning of the episode.