Plot Summary
Clear Sky is a prequel to the events in Stalker: Shadow of Chernobyl.
The player assumes the role of Scar, a veteran Stalker mercenary who was injured and rendered unconscious by an energy emission while guiding a group of scientists through the Zone. Scar, the lone and somehow lucky survivor, is rescued by Clear Sky, a secret and independent Zone faction dedicated to researching and understanding the Zone in order for humanity to better understand what kind of phenomena it is facing. It is not known how Scar survived, but it is noted he has suffered damage to the nervous system and now has an unusual characteristic around him. After becoming familiar with Clear Sky, a patrol at an outpost in the swamps is under attack and Lebedev requests Scar helps them out, especially as some of the men there saved Scar's life. After fighting off mutants keeping the team pinned, a second emission suddenly occurs. Scar is once again the sole survivor, recovered shortly after the emission died down. The leader of Clear Sky, Lebedev, is amazed by how Scar is still alive. The Clear Sky lead researcher, Chebekov, believes Scar has accquired some "unusual ability" that allows him to navigate and survive anomolies and parts of the zone that would practically kill any ordinary man. Lebedev begins to therorize that the Zone is being disrupted by a dramatic increase in energy emissions, emanating from the Chernobyl power plant in the center of the Zone. Human activity is believed to be the cause. In other words, the emissions are part of an "immune response" the zone has. Someone has made it to the center of the zone, which is supposedly "meant to be taboo" and the zone itself is trying to consume that person in order to preserve its secrets. Besides endangering all the Stalkers in the Zone, Scar is heavily at risk too, already badly damaged by both previous emmissions. Every emission harms the nervous system and future ones will eventually kill him if they continue. If the irregular and dramatic increase of emissions continues, the zone could eventually become highly unstable and run out of control, which may have disastrous and unknown effects for the zone and the outside world.
Scar is tasked with finding out about any activity regarding Stalkers trying to reach the center of the zone. The only peice of information he has to go on at first is that an unusual group of Stalkers were talking to the trader, Sidorovich, in the Cordon, the southern boundary of the zone. After assisting Clear Sky forces regain control of the swamps, Scar makes his own way to the Cordon, where he is contacted by Sidorovich. Narrowly escaping the Military outpost next to his entry point, Scar meets Sidorovich, who knows a great deal about what is happening in the Cordon and have met the stalkers Lebedev mentioned. He doesn't see a reason to stretch his memory about them until Scar asks if there is something that would make him talk. Sidorovich likes the idea of "talking business" and discusses his problem. Certain events have caused Loners and Military to turn on one another. The result makes a case of loot that the Loners were meant to deliver go missing. It doesn't do well for Sidorovich, as "the client is rare and the loot is rather unique". The deal is that if Scar can find and bring the case, Sidorovich will be shed some information about the stalkers. This can only be achievied if Scar co-operates with the Loners. As the leader Valerian reveals, Loners and the Military were fighting because the Loners were being double-crossed and ambushed by bandits, who were given locations of Loner activity. The only thing preventing them from being destroyed by the main brute of the Military is the captured commander, Kheletsky. He can't be set free and he can't be killed either. When Kheletsky refuses to reveal the lcoation, Velarian believes that they need to eliminate key forces who would attempt to rescue the commander. Doing this will force Kheletsky to crack. He eventually gives in and reveals the location of the case, which Scar collects and brings to Sidorovich.
Sidorovich, thanking Scar for bringing the case, is now willing to satisfy his end of the deal. He explains that the group that visited him were looking for some exotic parts he did not have in store, notably one of the members, Fang. Fang bought what he want from Sidorovich and when asked where to find the other parts he wanted, he was directed to the Garbage, where piles of old relics and unwanted objects similar to the request could be found. Scar heads to the Garbage to try and find Fang, but stumbles along a PDA belonging to a team that Fang double-crossed. After saving the messenger of the group who was pursuing, it is said that Fang ventured alone into the Dark Valley. Scar heads to the Dark Valley to find the Freedom faction, trying to control the area from mysterious attacks and losses of numbers of comrades. When Scar helps Freedom in order for information about Fang, he finds that mercenaries are being sent upon Freedom by a renegade commander who is attempting to flee. Scar helps Freedom deal with the mercenaries and the renegade commander, eventually clearing out their base of operations at an abandoned factory. To fulfill his end of the bargain, the Freedom leader tells Scar that Fang returned to the Garbage shortly after visiting the base for the parts he needed. Scar gets pointed to the Flea Market back in the Garbage and departs, hot on Fang's trail.
When he reaches the basement of the Flea Market, he is ambushed and is rendered unconscious by bandits. The bandits had laid the trap for Fang, in which they failed to stop him fleeing, now catching Scar instead. They care not about Fang, saying that he dropped his equipment and that's all that matters. They take Scar's equipment and run, leaving Scar alone. Lebedev hails Scar via PDA and tells him Fang's PDA is nearby. Upon discovering it, Lebedev's suspicions are correct. A message to Fang reveals that his friends are aware someone, assuming Clear Sky or Scar, knows that they've been to the center of the zone and there's a change in plans, which are detailed in a stash hidden in the Agroprom underground. Lebedev confirms that they are the ones the zone is trying to destroy, but its not clear how they got past the Brain Scorcher or why exactly they are doing this. Netherless, Lebedev reaches a conclusion. Either Fang and his friends are stopped or the zone will run out of control. Scar is tasked to pursue the team by any means possible. Before that, Scar will need to recover his equipment from the bandits who stole it, which is a difficult task as he has nothing to protect himself with except a leftover pistol.
He travels to Agroprom Institute, which is in the hands of Duty, the rival of Freedom. If Scar allies with Freedom, he will find it harder to complete this part of the plot. The zone is being overwhelmed by very dangerous mutants and the commander of Duty is hard pressed trying to remove them. When it is found that Fang went to the underground, Scar volunteers to head into there and rout out the mutants as a way to return the favour of information being spilled. Battling through mutants and bandits, he discovers the stash mentioned from the Flea Market. The log contains a recording from Strelok, the protaganist of Shadow from Chernobyl. His team, comprising of himself, Fang and Ghost, are going to head to the NPP once again, directly through the Brain Scorcher, in order to reach the Wish Granter. Their intentions clear, Lebedov gives Scar the undeniably difficult task of killing Strelok before he reaches the center. While Scar pursues him, Clear Sky will ambush and stop Fang and Ghost. After escaping the underground, it is time for the travel north, in which many obstacles await.
The first problem is in Yantar, a Loner dominant zone. The factory near the science bunker is swarming with hordes of zombies, ordinary people whose brains have melted due to a powerful psi field there. Professor Sakharov, who is operating in the area tells Scar that Strelok had passed through the region. While in Yantar, he volunteered to test a prototype device. In return, Strelok was allowed to keep the finished product. The device itself would allow the user to completely resist and block psi emission effects, like the Brain Scorcher. To help with the zombie problem, Scar locates a dead group of dead stalkers who were moments ago alive near the plant, with accquired notes about a cooling device in the plant designed to reduce psy emissions. However, the unstable field of recent is due to a failure in the system. In order to proceed, it needs to be repaired so that the psy emissions around the factory cease. Scar teams up with a Loner named Lefty and his crew who battle through the Zombie hordes and restart the coolant pumps inside the factory. Without the emissions, there should be no more problems. Professor Sakharov thanks Scar for his aid before informing him that a signal from the prototype device is being detected. According to the signal, Strelok is in the Red Forest. Scar quickly proceeds forward.
Strelok is directly in plain sight. Lebedev hurries Scar to stop Strelok, who responds with threats of death if the pursuit did not cease. After chasing him to a motorized bridge, an ambush springs from hired Loners and Scar must fend it off. Strelok takes advantage of this and is the sole escapee, blowing up a tunnel behind him. He assures Scar that it is no longer possible to follow him and clearly states that he will reach the center whatever it takes. Lebedev makes contact again. The tunnel was the quickest way to the plant, which is through the Brain Scorcher. The only possible way now is through Limansk, on the other side of the bridge. Lebedev tries to think of a way to reach the other side so. The bridge is raised, is sitting over highly radioactive water and controlled by bandits, who gaurded the operating console. Scar is directed to an old Forester in the Red forest, protected by Duty, who may know a way. Forester is regared as a famous guide in these parts, who can literally disocover safe parts in areas he has never been in before. Upon meeting Scar who navigates the forest, he tells Scar he knows of a way. A group of Stalkers and Mercenaries, guided by a man called Leshiy, were attempting to reach the other side but ended up in a spatial anomaly, effectively trapped somewhere near Limansk. They are unable to escape, as any attempts only brings them back at the start. To help them, Scar visits a group of Mercenaries aligned with Leshiy at the ravaged Military warehouses, who reported some radio transmissions appearing near a tower. When Scar arrives, he hears what is happening to the trapped group in the Spatial Anomaly. He then helps in recovering a unique artifact for Forester which enables him to navigate the zone. Forester believes it could to used to help guide the team out of the anomaly. One task remains. Scar must deliver the group co-ordinates that will help them leave and free themselves from the anomaly.
Scar is directed back to the Military warehouses, where he reunites with the mercenaries. They know of a military radio transmitter which is powerful enough to transmit the needed coordinates to Leshy's team. Unfortunately, it is guarded at a base by what is believed to be the last of the Military. The Military have been reduced significantly down to a few squads because they could no longer hold the barrier. The leader, Hog, pairs Scar with Kostian, a freedom stalker leading an attack squad who are making a raid at the same place and owes Hog for being rescued weeks ago. After fighting heavy resistance at the base, Scar powers up the transmitter and waits as Leshy and his team is freed. They are now on the other side of the bridge. Lebedev acts on this action. Convincing Leshy and his team to aid Clear Sky in reaching the other side, a large contingent of Clear Sky soldiers head to the bridge, awaiting Scar's arrival so they can make a push. When he does get there, he assists Lebedv and the Clear Sky forces to provide cover from bandits for Leshy's team while they lower the bridge. After a heated battle, both sides succeed and share thier grattitude. Clear Sky then begins to make the push through Limansk. Lebedev tells Scar to join the first advance team and spearhead the charge.
The pressure is on at this stage. Limansk has been turned into a street war between bandits, remaining Military forces and, if Scar did not encounter them at the barrier in the Military Warehouses, Monolith. Clear Sky helps Scar push foward, having to face many obstacles. Monolith has heavily entrenched themselves within the city in their attempt to prevent anything and anyone from reaching the NPP. Scar faces many osbstacles, such as clearing out machinegun emplacements cutting power to electrical fences blocking the way out of Limansk. Once he has made it past, the only thing that's left is the underground part of an abandoned hospital. Another advance team is pinned down by Monolith, who are swarming in large numbers. Scar and Clear Sky forces work together to make a push through the hospital so they can get to the NPP. There is harsh resistance, but Scar pulls through. But during the process, an Mi-17 (Mi-8MT) helicopter controlled by the Military appears, opening fire on everyone in the Hospital, including Scar, and preventing progress. Scar eventually defeats the helicopter alone while the advance team catches up. After clearing passage to a network of tunnels, the advance team stays behind, giving Scar a window to reach the NPP.
The final battle is at hand. Strelok is within the vicinity, attempting to break through Monolith, Clear Sky and surprisingly Duty, who have somehow reached the centre and are taking up arms against Monolith. Lebedev thanks Scar for helping them reach the center and now needs his help to settle the score once and for all. Given a prototype Electromagnetic Pulse (EMP) Gauss Rifle, Scar must use it to disrupt the psy-blocker device on Strelok. Without the aid of the device, Strelok will not last much longer from the psi emissions. The activity in the zone is also believed to stabalise after Strelok is defeated. Fighting his way through Monolith on the upper parts of the NPP, Scar uses the Gauss rifle to disrupt the device which he succeeds in doing. Strelok is defeated and readings are taken to see if the stabilising is beginning. But to Lebedev's horror, an unexpected and massive emission occurs, reaching levels beyond the norm. Everyone within radius of the plant, Duty, Clear Sky or otherwise are hit and begins succumbing to the effects of the emission. During the Outro, they can be seen shaking unnaturally, crowded in corridors where brief and blurry black and white images on screens flash violently in their faces. These signs indicate that those whose lives weren't taken from the blast end up with a worse fate. They would seem to be in the process of being brainwashed to become part of the Monolith forces, or, like Strelok, become unwitting agents of the C-Consciousness.
From there, the Shadow of Chernobyl version of the zone unfolds and the story continues as seen in Strelok's point of view.