Half-Life 2: Episode One storyline

This article describes the Half-Life 2: Episode One storyline, chapter by chapter.

Undue Alarm


Following the events of Half-Life 2, Episode One starts out with Gordon experiencing some kind of vision that lets him review the explosion of the Citadel's Dark Fusion Reactor. As time stops, several purple glowing Vortigaunts appear and rescue Alyx Vance. The G-Man is then seen walking through the door made of light toward Gordon Freeman. As he opens his mouth to say something, he is distracted by blue lights and is separated from Gordon by another group of Vortigaunts. Several of them surround the G-Man and block him off from Gordon with a blue energy shield. He straightens his tie and looks at Gordon while saying in an irritated tone: "We'll see...about that." More Vortigaunts then surround and teleport Gordon, in the same manner as Alyx, removing them both from stasis.

Gordon wakes up outside the Citadel, buried under a pile of rubble. Dog removes these rocks, and Gordon is reunited with Alyx. Alyx contacts Eli Vance and Isaac Kleiner through a monitor, and Kleiner tells Alyx that the Citadel Core is at risk of exploding at any moment. Kleiner states that the explosion could be large enough to level the whole of City 17, and that the only possible way to survive would be to re-enter the Citadel and slow the core's progression toward meltdown. Eli interrupts, showing distress at placing his daughter in further danger, but reluctantly agrees when he sees no other option. Alyx and Gordon re-enter the Citadel to try to reactivate the stabilization mechanism for the core, averting disaster.

Direct Intervention


This chapter consists of Gordon Freeman entering the core to help slow down the meltdown. Afterward's they make their way to one of the still running Razor Trains and begin their journey to escape the city.

During their time in the Citadel, they discover a recording of the discussion between a Combine Advisor and Dr. Breen before Gordon chased him down in Half-Life 2. Breen reprises his words from HL2, saying:


 * "It's me you should be worrying about. I can still deliver Earth, but not without your help... The portal destination is untenable, surely you can set the relay elsewhere. There's no way I can survive in that environment... A host body?! You must be joking! I can't possibly- Oh alright, damn it! If that's what it takes. Just hurry, he's right behind me! Oh shi-"

The recording ends, interrupted by a brief image of a Combine Advisor. Alyx and Gordon are then subject to psychic blasts as an Advisor Pod is transported through a tube in the control room.

Later on, Gordon and Alyx are successful in re-engaging the reactor's containment system, delaying the explosion. Alyx subsequently discovers that the Combine are trying to use the reaction, and therefore the destruction of the Citadel, to send a message to off-world Combine forces. The message is from Judith Mossman, she is in a arctic environment north from City 17. She is talking about a Project which her and her team has discovered, but the Combine attacks the base and she had to cut the transmission. She is able to run away, presumably to safety, before Combine troops invade the area she had been filming in. Alyx makes a copy of the message packet to take to Dr. Kleiner and Eli, ensuring that the Combine make them their prime target and even in their disorganized state attempt everything they can to stop them.

Alyx and Gordon then board a Razor Train to escape the Citadel. It becomes apparent that the carriage Gordon and Alyx are in is being used to transport Stalkers. Alyx mourns for the Stalkers and is then interrupted by the train derailing, which wakes the Stalkers.

Lowlife


This chapter is Gordon and Alyx fleeing through the city's ruined, dark, and zombie infested underground as they continue to flee the city.

Alyx is trapped under a pod with a restrained Stalker viciously attempting to break loose, relying on Gordon to set her free. After escaping from the train, the duo fights through the rubble of dark, deserted, underground parking garages and tunnels, searching for a way to head up to the surface of the city. In the process, they block off Antlion burrows, and battle various zombies in a pitch black environment, including zombified Combine soldiers, which were never seen during Half-Life 2.

Urban Flight


In this lengthy chapter, Gordon and Alyx work their way through the city streets and a dangerous hospital before meeting up with Barney to make their way to another train station so they may finally escape.

Eventually, the duo manages to find the exit of an underground train station and Gordon and Alyx come up to the surface, observing the citadel from afar, and the destruction already visited on City 17. Dr. Kleiner appears on the screens that Breen used to pass out propaganda, mentioning that the Suppression Field, which had previously prevented human reproduction, is down. As the duo moves on, they engage in several fights with Combine soldiers, Antlions, and zombies.

Alyx and Gordon finally meet up with Barney Calhoun and a group of other survivors who are preparing to move on a train station in order to escape City 17. With the Combine still following, Gordon and Alyx split up from the group and move through a derelict hospital to draw the remaining Combine forces away from the refugees. Inside the hospital, Combine forces and zombies of all kinds are fighting throughout the collapsing structure, and hastily constructed defences slow Alyx and Gordon down.

Exit 17


In the final chapter. Gordon helps evacuate citizens and rebels and fights a strider blocking the train tracks. The Citadel blows at the end of the chapter, and its shockwave overtakes Alyx and Gordon's train.

Upon reuniting with Barney at the train station, Alyx and Gordon work to move the citizens to the trains while facing increasing Combine opposition. They then decide to stay behind to lure the Combine away from Barney and the citizens as they board the train and make their escape.

After battling Combine soldiers and a Strider, the duo reprogram another train and board the caboose. As the train carries Alyx and Gordon away, the Citadel is visible in the background with the reactor core once again about to explode, and the Combine's message is sent. Several pods similar to the one containing the Combine Advisor in the control room are ejected from the Citadel as it detonates. On two occasions, as pods pass overhead, Gordon and Alyx are hit with psychic blasts. The force of the shockwave from the exploding Citadel causes metal chunks and wreckage to fly toward the train Alyx and Gordon are on as it sends its final transmission, and the screen fades to an ominous white as the shockwave overtakes the train. The last thing that the player hears is the twisting of metal and Alyx whispering Gordon's name. The screen then fades to the credits.

The plot continues from this point in Half-Life 2: Episode Two.