This subject is from the Black Mesa Incident era.

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Gordon Freeman wielding his trademark crowbar in front of the Blast Pit Tentacles, while a pair of security guards fall to their deaths in the background.

This article describes the Half-Life storyline, chapter by chapter.

Hazard Course (optional)

"Hello, and welcome to the Black Mesa Hazard Course"
Holographic Assistant[src]

The Training Facility at Black Mesa houses the Hazard Course to help users of the HEV Suit hone their skills at jumping, crouching, and combinations of both movements in an environment as well as to give them basic instructions on how to operate guns and interact with the rest of the equipment.

Chapter 1: Black Mesa Inbound

"This train is inbound from Level 3 Dormitories to Sector C Test Labs and Control Facilities"
Black Mesa Announcement System[src]

Gordon Freeman rides the tram to his underground lab at 8:47 AM and passes Barney Calhoun, seen bashing on a locked door as Gordon continues his trip. The public announcement system announces the most recent news, making ironic comments about healthcare measures on radiation and urinalysis tests, as large pools of radioactive waste pass beneath him.

Doors open and close as he goes slowly underground to the test chamber. From the windows, Gordon can see nuclear missiles ready for transport to launch sites, robots nearly crashing into the tram, and the intricate workings of the Black Mesa Research Facility revealing themselves as being fragile, and more often than not, broken.

At a Loader crossing, the tram is stopped, and on the left, the G-Man is as well in a tram. Eventually, Freeman's tram reaches its destination, and after stepping out onto the catwalk, Gordon's day begins.

Chapter 2: Anomalous Materials

"They're waiting for you Gordon... in the Test Chamber"
―A scientist reminds Gordon of his duty[src]

Arriving at the Anomalous Materials Laboratory, his usual place of work, Gordon dons his HEV Suit. Continuing down to the lab, Gordon finds himself face to face with the people conducting his test; they inform him that they have a unique and large sample of a classified origin and that they will be deviating from normal procedure to accommodate for this.

Once in the test chamber, he goes to the control panel and presses the button to start the rotors on the Anti-Mass Spectrometer. Rising up from the delivery system, the sample arrives. "Standard procedure for a non-standard specimen," they assure him from above. "Go ahead, Gordon." Gordon proceeds to push the cart into the beam.

The scientists begin to tell him to stop the Anti-Mass Spectrometer, but he is unable to hear them. Everything goes black. All that can be heard is the sound of his heavy breathing. Another flash of green, and he's on a strange alien world. Just within the pool of green light around him, odd-looking bipedal lifeforms stare at him, as if confused. Another flash of green and he's back in the destroyed test chamber.

Chapter 3: Unforeseen Consequences

"Prepare for unforeseen consequences."

Black Mesa has received massive structural damage, and to make matters worse, aliens from Xen begin to flood into the facility. After being told that all phones are out, Gordon is requested by his colleague Eli Vance to try to make it to the surface in order to acquire help.

Gordon finds a crowbar to help him get past obstacles. Since the tram is too damaged to work, he must cross Sector B's Coolant Reserve Facility in order to find a way out.

Gordon occasionally witnesses G-Man watching him from out-of-reach places, always walking off before Gordon can get to him.

Chapter 4: Office Complex

"Hey! What the hell are you doing down here? Get topside! I heard there are troops coming in to save us."
―A security guard[src]

Gordon reaches the office complex, where several scientists and security guards are barricaded into their rooms, hiding from the Xen creatures that keep coming. He hears from the personnel that the military have arrived to rescue the people trapped in the facility.

Chapter 5: "We've Got Hostiles"

"We've got hostiles!"
HECU Marine[src]

Gordon begins making good progress, passing through various storage and staging areas, continuing his hunt for a way to the surface. Gordon learns that the soldiers coming on a rescue mission have already arrived. He attempts to join up with them but walks into a room and witnesses a Marine killing a scientist. It is then that he discovers that the Hazardous Environment Combat Unit (HECU), which has taken control of Black Mesa, is not just killing the aliens, but is targeting everyone connected to the project to keep a media circus from beginning.

When he eventually reaches the surface, Gordon finds the facility under total control of the military and, worse, in the middle of an artillery bombardment. Taking cover, he is forced back into the underground complex. However, it is stated by a scientist that the surviving members of the Lambda Team (in the Lambda Complex at the other end of the facility) may be able to close the dimensional rift. Therefore, Gordon begins the journey across Black Mesa to reach them.

Chapter 6: Blast Pit

Gordon enters an abandoned, largely sealed-off area of Black Mesa dating back to its earlier days as a missile complex, full of mothballed machinery and now used as a dumping ground for toxic waste from the rest of the facility, where the HECU soldiers have yet to get a good foothold because of the overwhelming amount of aliens and toxic waste in the area.

Arriving at a rocket engine test silo, Gordon discovers the Tentacle. After reactivating the fuel, power, and oxygen lines, Gordon is able to kill it by using the rocket engine to incinerate it and finds a way out through the meters-long dirt tunnel dug by the Tentacle.

Chapter 7: Power Up

Trying to reach the surface once more, Gordon's progress is thwarted by a Gargantua in the Sector E Materials Transport. He then learns from a dying security guard that if he restores the generator, he can ride the tram to the surface.

Freeman enters the Houndeye infested subterranean areas and activates the generator, restoring power to sector E; after activating more switches, he destroys the Gargantua patrolling the area by turning on the transformers supplying the rail system with power. It is also possible to kill the Gargantua using an excessive amount of explosives.

Jumping onto a tram, he is able to continue his way by smashing through the concrete barricade blocking the access to the rail system.

Chapter 8: On A Rail

As Gordon rides the tram into the Materials Transport section of Black Mesa, he learns from a security guard that he must ride to the High Altitude Launch Center to launch a satellite, which the Lambda Team can use to reverse the effects of the Resonance Cascade.

Freeman also discovers the HECU's true hatred for him, as well as their larger reinforcements: sandbag bunkers with rapid-fire sniper rifles, mounted machine gun turrets (manual and automated), and even mounted rocket launchers.

After going round in circles for a while, Gordon goes up several elevators and at last reaches the surface again near the launch site; he sends the rocket up into orbit and goes back underground.

Chapter 9: Apprehension

Continuing towards the surface, Gordon encounters a terrifying new aquatic Xen creature, the Ichthyosaur, and acquires a deadly new weapon to fight it. After an underwater battle with an Ichthyosaur, he manages to escape and get back on his way.

After battling with the Black Ops, another military crew trying to eliminate even the HECU, Freeman is captured by two HECU soldiers. Instead of taking him in for questioning, out of spite, they remove all of his weapons and drop him in a trash compactor.

Chapter 10: Residue Processing

After escaping from the trash compactor and getting back to the surface, Gordon stumbles towards a mostly abandoned part of the facility, meant for processing and disposing of waste and hazardous materials.

Dodging and jumping through antiquated compaction machines, large vats of waste, and slipping through furnaces, as well as riding on gravity-defying conveyor belts, Freeman leaves this part of the facility.

Chapter 11: Questionable Ethics

Gordon eventually winds up in a secret part of the facility where he discovers that scientists had been "collecting" specimens from Xen since long before the incident occurred.

Inside, Freeman continues to rearm himself to rejoin the battle against the HECU. He also meets the alien military units, the Alien Grunts; and finds one of the most powerful weapons in the facility, the Tau Cannon. Soon, he heads outside to search for the Lambda Complex.

Chapter 12: Surface Tension

Gordon again reaches the surface, which is now a war zone. The Vortigaunts, along with Alien Grunts and Gargantuas, have begun making determined attacks against the Marines, and the tide of the battle is beginning to turn in favor of the aliens; the Marines call in reinforcements, but it is not enough. Gordon must scale cliffs and navigate the bombed out buildings while avoiding both sides.

Many skirmishes are seen between the HECU and the Xen forces. Finally, Gordon reaches relative safety underground.

Chapter 13: "Forget About Freeman!"

"Forget about Freeman! We're abandoning the base! If you have any last bomb targets, mark them on the Tactical Map, otherwise, get the hell out of there!"
―HECU commander[src]

The HECU determines that they are fighting a battle they cannot win against the Xen aliens. With this, as well as having continually failed to neutralize Freeman, they abandon their mission and begin to evacuate the facility, calling in air strikes and heavy artillery to cover their retreat.

Gordon enters an underground storage garage to avoid the bombardments, and eventually fights his way through scores of aliens and several groups of the decimated HECU forces before reaching the Lambda Complex.

Chapter 14: Lambda Core

After much struggle, Gordon finally reaches the Lambda Complex, which he discovers to be the place where Black Mesa developed the teleportation technology that allowed scientists to travel to Xen in the first place.

The handful of surviving personnel, who have held themselves up in a small stronghold, inform Gordon that, the satellite he launched earlier was not able to reverse the effects of the Resonance Cascade because an immensely powerful being on the other side is keeping the rift between the worlds open, and Gordon must go to Xen to kill it and prevent the aliens from taking over completely.

Before being teleported to Xen, Gordon gains access to an arsenal, health and HEV-charge caches, and is finally given the Long Jump Module. After an attempted interception by Alien Controllers, the scientists open a portal and Gordon jumps in.

Chapter 15: Xen

Once in the border world of Xen, Gordon encounters many of the aliens that had been teleported into Black Mesa in their natural habitats, as well as the remains of some HEV-wearing researchers who came before him. In order to progress, he needs to re-activate a portal inside one of the floating islands to venture more of Xen's perimeters.

Chapter 16: Gonarch's Lair

Freeman is made to face one of the Nihilanth's most powerful minions; the Gonarch, found in its lair, located in another floating island. Gordon is able to kill it and use the portal created after its death to continue.

Chapter 17: Interloper

Gordon's journey across Xen continues, but his supplies are running short, spent on destroying the Gonarch. He is teleported to an Alien Grunt cloning facility, where the army of Xen is created. There, Gordon finds a group of docile Vortigaunts working, before exiting the facility and getting ready to enter one last teleporter.

Chapter 18: Nihilanth

"Win, you cannot win."
―The Nihilanth taunts Gordon[src]

In a vast cave, Gordon finally confronts the powerful and mysterious being that is holding the portal open, the Nihilanth. Gordon destroys its healing system, allowing him to destroy its vulnerable brain. As the creature dies, it floats toward the ceiling, emanating portals, and finally exploding in a giant green blast that overpowers Gordon's senses.


"Time to choose."
―The G-Man[src]

When Gordon comes to his senses, he finds himself in front of the G-Man. Both are transported to various locales around Xen, while the G-Man praises Gordon's actions in the border world, to later explain that his "employers" have agreed that Gordon has "limitless potential," and have authorized him to offer Freeman a job.

The G-Man and Gordon are teleported a last time to a tram car, flying through space at immense speed. By stepping into a portal, and knowing that his only other choice is a battle he has no chance of winning, Gordon accepts the G-Man's offer.

Finding himself floating in nothingness, he hears the G-Man's voice one last time; "Wisely done, Mr. Freeman, I will see you up ahead..."

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