This Call of Duty: Modern Warfare 4 guide summarizes the story and explains the ending. It covers the whole MW4 campaign, including who dies by the end and how it all sets up DMZ. This article has major spoilers for the full campaign. If you have not finished it yet, you may want to come back later. The campaign has two stories running side by side. One follows Captain Price on a personal mission, and the other follows the war on the Korean Peninsula.
MW4 Story Summary
Spoilers ahead. Here is how the story unfolds:
Price’s Mission
The story picks up after Modern Warfare 3, with Price working on his own and wanted by his own side. He believes Makarov is not the one in charge. In his view, a hidden person is pulling the strings, and that person is known as The Archer. Price goes after Makarov and the people around him, including Milena Romanova, who is linked to his money. Price kills Makarov. Along the way, he also takes down Andrei Nolan and Commander Graves.
Price also crosses paths with Valeria Garza, who is part of the search for a dangerous weapon tied to The Archer. His old friends Ghost and Gaz are drawn into the chase as well, and they end up on the opposite side of Price at one point.
Gaz
Gaz dies during the campaign, but the story does not stop to explain it. We never get a full picture of what he was trying to tell Price before he was gone. What is left is his voice. In the final mission, Price hears Gaz in his head, replaying their old talks about where to draw the line. By the time Price reaches The Archer, those words are all he has left of his friend.
The War in Korea
At the same time, North Korea invades South Korea. Supreme Leader Ri is one of the people behind it. She wants the whole peninsula under North Korean control, and she took power by arranging the death of her own brother, who was the leader before her. He was not keen on such an aggressive plan. Ri has help from The Archer, who is a member of Russia’s Ministry of Defense. He supplied a weapon that gives North Korea a big advantage.
You spend most of the campaign as Pvt. Park Hyun-Jun, a US Marine who is only serving because he has to. He fights alongside South Korean special forces, the CIA, and other Marines to push the invasion back. By the final stretch of the Korean War, the Allies have already taken back some important ground.

The Ending Explained
Even more spoilers. This time, we look at how the MW4 campaign ends:
The Strike on Ri
The Korea story ends with an off-the-books mission to the North Korean Presidential Palace. The CIA, the Marines, and South Korean special forces go in with one goal, which is to kill Ri. They succeed. This mission is called Decapitation.

What Happens to Ko
Ko is a North Korean officer who turned on his own government. He used to serve Ri, but he changed sides after seeing how she treated her brother and her own people. When the fighting stops, he chooses to stay in North Korea. He hopes to help his country move in a better direction.

Park’s Choice
Park starts the game wanting to finish his service and leave the military. That changes during the war. He builds a bond with Kal, the captain of the South Korean special forces, who sees potential in him. After the last mission, Jae asks Park what he wants to do next. Park seems to be thinking about staying and even joining the special forces. The game does not say it for sure.

Price and The Archer
Price’s story ends in the final mission, Greater Good. The Archer has taken Price prisoner and plans to cross the Russian border with him and one of the two weapons. One weapon stayed with Ri, and The Archer kept the other. With Ri dead, he is taking his weapon home.
The Archer does not want to simply kill Price. He wants Price to suffer. Earlier in the campaign, he talks about destroying the people Price cares about. There also seems to be a personal reason behind it. The Archer learns what Price did to Makarov, and Makarov was his son.
Ghost finds the transport and makes it crash, which gives him a chance to save Price. Price is badly hurt in the crash and has a serious wound to his stomach. Ghost holds off the soldiers while Price pushes on toward The Archer. As he goes, he hears Gaz’s voice in his head. He seems to understand now what Gaz was trying to tell him about crossing lines.
Price reaches The Archer and kills him. After the fight, Price lies on his back, and his injuries catch up with him. Ghost arrives and slowly lowers his weapon. He asks Price whether it was worth it. Price says Gaz was right and that you have to hold the line instead of crossing it. Ghost answers, “Good to see you again, John.”
Price dies with Ghost beside him. Ghost closes his eyes, takes the weapon the Archer was carrying, and walks away.

The Twist: Makarov Was The Archer’s Son
One of the biggest twists in the campaign is that Makarov is The Archer’s son. It is only mentioned in passing, so it is easy to miss. It changes the whole story, because it explains why The Archer goes after Price.
In Out in the Cold, Price corners Makarov in a New York alley and beats him to death. At that point, Price is only killing a man he has hunted for years. Later, The Archer sees what Price did to Makarov, including his disfigured face and broken arm. That is when the war becomes personal.
From then on, The Archer is not only after the weapon. He threatens to destroy everyone Price cares about and to make him watch the West fall. When he captures Price, he does not kill him. He keeps him alive so he can suffer first. This is why the final mission feels so personal. It is a father getting revenge for his son, and Price’s earlier mission to stop Makarov is what started it.
Laswell and the Watcher Program
A last scene shows Kate Laswell. She deletes all of her files on Price, Ghost, and Gaz. She then meets a woman whose face we never see and tells her that operations are moving into the DMZ. Laswell says she has recommended her as her replacement and welcomes her to the Watcher program. Fans think this woman is the handler who gives Ghost his orders in the DMZ, but that is a guess.
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How MW4 Ending Sets Up DMZ
DMZ takes place after the campaign, though we do not know how much time has passed. The power plant disaster has spread radiation across the area near Hajin, and people have left. North Korean forces are moving back in because there is a large network of military sites under Hajin that holds chemical, biological, and nuclear weapons. Outside contractors and rogue groups have also entered the zone, looking for the same weapons and information.
Ghost is back in the middle of this, taking orders from a handler. The plan is for him to clear threats, gather intelligence, and stop the weapons from falling into the wrong hands.
There is also a Russian angle. The Archer was part of Russia’s Ministry of Defense, so his role in the invasion could cause trouble for Russia, and his death near the border could cause trouble for the West. The developers have talked about Russia becoming more involved in the DMZ over time. We do not know how yet.
Modern Warfare 4 closes some long-running stories. Price and Gaz are gone, Task Force 141 is shut down, and the story moves to a new group in DMZ.
FAQs
Yes. Price is badly hurt after the transport crash in the final mission, Greater Good. He kills The Archer, then dies with Ghost beside him.
The Archer is a member of Russia’s Ministry of Defense who helped North Korea with the invasion. He is voiced by Mads Mikkelsen. He also supplied one of two powerful weapons, and he kept the second one himself.
Laswell deletes her files on Price, Ghost, and Gaz and steps back from the Watcher program. She then hands it over to a new handler as operations move into the DMZ.