The Scarlet Nexus plot is packed with twists and turns, along with a lot of information and history. The dual narrative structure along with the vast amounts of exposition can sometimes be tricky to follow. As such, I’ve put together a full summary of the story, attempting to answer as many major questions as possible. Granted, not everything is fully explained within the game itself so there’s the odd bit of speculation.
With obvious major SPOILERS, here’s a full explanation of the Scarlet Nexus plot, told in a rough chronological order and not always the order provided during the game. Although the specific ending details come later on in the article, I would still recommend reading the full plot recap, which includes explanations of things that weren’t always clear at the time.
- RELATED: Scarlet Nexus Review
The moon and the extinction belt
Some 3,000 years before the events of the game, the Earth had become completely uninhabitable due to pollution and environmental disaster. To save the species, humans fled to the moon where they worked on technology would hopefully enable them to survive the threats on the planet and return.
It took 1,000 years, but eventually humans developed the means to reinhabit Earth. Colonists were sent back, including Yuito’s ancestor Yakumo Sumeragi, also stopping the moon from becoming overpopulated. Around the same time, a comet passed by the moon, which brought with it cosmic Other particles which turned living beings into mutated creatures. The dangerous particles created panic on the moon, but the colonists managed to avoid it and reached Earth unscathed.
Using their advanced technology, those on the moon were able to harness the Other particles into the Extinction Belt, which was wrapped around the Earth. This is essentially a continuous supply of Other particles, producing repeated waves of monsters as well as blocking travel and communication to and from Earth. The occupants of the moon repeatedly sent animal genetics into the extinction belt, causing Others to frequently drop onto Earth in various forms, and keeping the inhabitants of Earth isolated and under attack.
The colonists from the moon ended up splitting into two factions. Those led by Yakumo Sumeragi founded New Himuka, which started repopulating the Earth once again. The other faction – including Kagero – became Togetsu, and was founded by a woman named Dr Pope. They desperately wished to return to the moon, but were now cut-off due to the Extinction Belt. Togetsu formulated a plan to develop and research the power of the Red Strings to go back in time and prevent the last 3,000 years altogether, theoretically stopping the colonists leaving the moon in the first place.
Among the population of Earth at the beginning of the game, this was not common knowledge. The vast majority know nothing of the moon and simply believe civilisation was founded by Yakumo Sumeragi at the time of a battle known as the Spring of Extinction, which is when they also believe the Extinction Belt appeared. During this conflict, which isn’t really expanded upon, Yakumo became a hero to the people of New Himuka but suffered a facial injury that caused him to wear a mask.
The OSF and Naomi’s metamorphosis
At the start of both routes, the respective protagonists join the New Himuka OSF. Yuito has a memory of Kasane saving him as a child, but they otherwise both lack childhood memories. After carrying out training and early missions with their separate platoons, they are called to assist with a situation in the Abandoned Subway.
During a conflict there, Kasane’s sister Naomi is shot by a bullet that metamorphosises her into an Other. The party fight Naomi in her new Other form, before she is transported away by agents of Seiran, the other main settlement in the area. Most of the characters do not witness Naomi’s transformation, but Yuito’s best friend Nagi is one of the few who saw it occur.
Nagi is taken away for ‘Personality rehabilitation’, causing him to forget this event altogether. Meanwhile, Kasane tries to chase Naomi down and encounters Karen, who is distrustful of New Himuka and swears her to secrecy. She soon learns that he is planning a rebellion against New Himuka alongside the city of Seiran.
This culminates in a battle on the Kunad Highway, where Yuito and Kasane’s platoons both appear at the same time. Someone else is metamorphised into an Other by a New Himuka agent, so Kasane suspects New Himuka also caused Naomi’s metamorphosis. Nagi is also present at the highway but due to his personality rehabilitation, he enters into a rage with enhanced powers. He attacks Yuito and Kasane and is repelled by Yuito’s platoon leader Seto, who dies in the processs.
Kasane has grown to respect Seto, so the shock of this event causes her power to lose control. The identical powers of Kasane and Yuito resonate, bonding together to form the Kunad Gate, akin to a black hole. They briefly enter a dimension where they witness New Himuka’s founder Yakumo Sumeragi being assassinated, which comes as a surprise. The Kunad Gate remains in place, and Yuito’s powers are actually maintaining its presence. It gradually grows bigger as he uses his psychokinesis more.
Due to the Red Strings, Kasane and her platoon are propelled 50 years into the future. She meets a future version of Yuito, who explains the Kunad Gate will soon envelop the whole world, and the only way to stop it is to kill him in the past, due to the fact his power maintains it. He explains their psychokinesis is actually gravikinesis, capable of time travel. He sacrifices himself to shock Kasane into using her time travel powers again to transport back to her own time, which succeeds. She ends up back in present-day Suoh, New Himuka.
As a precursor to his rebellion, Karen has disabled New Himuka’s defences and caused Others to attack the city. Yuito arrives just in time to see his father Joe Sumeragi killed, with Kasane standing over the body. In actual fact, Kagero was the culprit before turning invisible. Heeding future-Yuito’s instructions, Kasane attacks Yuito in order to kill him and prevent the Kunad Gate expanding further. The platoons withdraw when an announcement of rebellion from Karen interrupts the battle, sending the teams in different directions.
Uncovering experiments and conspiracies
Future missions from both platoons reveal the objectives of the respective factions. New Himuka have been conducting numerous experiments. They secretly developed metamorphosis techniques, to turn humans into Others as well as ‘personality rehabilitation’ to brainwash people who find out about this, along with anyone who may become problematic. During a journey to the old OSF hospital, Yuito also finds out he was born without powers, and further experiments artificially provided him with his psychokinesis.
New Himuka wish to weaponise Others for battle, but they also want to destroy the Extinction Belt. We later learn from Yuito’s brother Kaito, a prominent member of the government, that they ultimately want to exact revenge on the people of the moon, who they believe purposely trapped the colonists on Earth. Kaito reveals they don’t care if it requires the sacrifice of civilian brains to achieve this end, and this was the will of Yakumo Sumeragi (though – as we find out even later, it wasn’t actually him).
Kasane’s platoon joins Seiran’s rebellion, who want Yuito killed to close the Kunad Gate. Seiran are also experimenting on Others and feed them with human brains. They have found a way of temporarily restoring metamorphised Others to their senses, and are attempting to find a way to transform them back into humans. This includes Naomi, meaning Kasane’s goals align with Seiran. Since Seiran are holding Naomi in their facility, they later use her as leverage to ensure Kasane fights Yuito’s platoon. Seiran can use human brains to convert non-metamorphised Others into weapons, and want the Extinction Belt to remain, which is where they mainly differ in objective to New Himuka.
Togetsu and Kagero
After clues point in its direction, the parties respectively travel to Togetsu and learn the truth of its existence. Namely, that it isn’t a religious sect and their wish is to return to the moon by utilising the Red Strings. Kyoka and Kasane are among Togetsu’s ‘Design Children’, who are artificially created with specific objectives. The Togetsu colonists that came from the moon are generally kept in cold sleep to oversee the progress of their plan.
Kasane was provided with Red Strings power, which needed to manifest and strengthen for Togetsu to use it. Kyoka was given Dr Pope’s memories, along with an objective to observe Wakana, who was a Red Strings user among Togetsu’s ranks and became a foster parent to Kasane before fleeing to New Himuka. Kasane herself left Togetsu and was adopted into the Randall family some time after this, but the details of exactly how this occurred are limited.
At New Himuka, Wakana met Joe Sumeragi and gave birth to Yuito, who also developed Red Strings power whilst Kyoka monitored them. However, over time Kyoka’s own personality supplanted the memories of Dr Pope along with her Togetsu orders, meaning she was eventually able to use her own free will, unlike many of the other Design Children.
Togetsu try to capture Yuito and Kasane, whose dual Red Strings powers now may be able to enact their plan of mass time travel, but the platoons help each other out and escape. After this, Kagero’s true intentions are revealed. He was a colonist who ended up in Togetsu’s ranks, but he did not support their plan. He wanted to stop them erasing the past as it would have also erased the life of his daughter, who was left on the moon. In order to remain amongst Togetsu and hinder them from the inside, he had to continue carrying out certain orders to avoid suspicion. Unfortunately, one of these orders was the assassination of Joe Sumeragi, which got pinned on Kasane for a while.
This assassination may seem a bit pointless, but Kagero is the one who helps break Kasane out of her cell during their platoon’s trip to Togetsu. Perhaps the fact he was still in their good books at this point was actually for the best.
Karen and the Kunad Gate
Now fully abreast of the dynamics between the warring states of New Himuka and Seiran, Yuito’s platoon use the super-computer Arahabaki disseminate information amongst the New Himuka citizens that they are effectively primed to become sacrificial lambs in a revenge mission against the moon. This causes unrest, and the platoon encounter Karen in the process.
It transpires Karen’s wider objective is to save Alice, an OSF comrade who was Fubuki’s fiancé but got metamorphised into an Other during a mission. His goal was to restore her to human form, which is why he teamed up with Seiran.
Kasane’s platoon, meanwhile, find out that the Others who were originally human are about to be weaponised and deployed by Seiran. In the struggle to prevent this, along with an attempt by Togetsu to recapture Kasane, these Others are killed. This includes Naomi and Alice, the very woman Karen has been trying to save. Upon Alice’s death, he realises the only way to save her now is to copy the powers of Yuito and Kasane and use the Red Strings to time travel and prevent her metamorphosis in the first place.
The platoons turn their focus to closing the Kunad Gate – preferably without killing Yuito. As the centre of Red Strings research, they believe Togetsu holds the key, but when they journey to their own super-computer archive (BABE), it shuts down. There is still one person who may hold the key – Wakana, who was a Red Strings user herself but died prior to the game’s events. During this escapade, Yuito and Kasane realise they share the same mother.
Kasane travels back in time with the Red Strings and meets up with Wakana on the day she died, saving young-Yuito’s life in the process. Kasane brings Wakana to the present day, and they learn that BABE’s shut-down actually imported its Red Strings research to past users including Wakana. She explains that the Kunad Gate can be closed if they enter the Chronos Terminal within and unravel the entanglements – essentially, any trace of people who journeyed through time must be erased.
Kasane and Yuito unravel the entanglements – Kasane’s journey 50 years into the future where she met future Yuito, along with her trip to the hospital where she saved Yuito’s past self. Wakana must also return to her time, where she knows she will be ambushed and killed by Togetsu. Her death will eliminate the entanglement created when she travelled to the future with Kasane.
This still doesn’t close the Kunad Gate, as there is one entanglement remaining – Yuito and Kasane realise Karen travelled into the past, where he assassinated Yakumo Sumeragi 2,000 years ago. This version of Karen has actually been hooked up to Arahabaki for the entire period, absorbing its knowledge and power whilst in cold sleep. Multiple versions of present-day Karen have also been time-travelling over and over, trying to save Alice to no avail.
Yuito’s brother had previously revealed that Yakumo Sumeragi was alive, so the platoons now surmise this is Karen. They venture into Sumeragi Tomb and plead with Karen to unravel the final entanglement to save the world. After defeating Karen in battle, he finally agrees to close the Kunad Gate. Using the combined power of Arahabaki and all Red Strings users, they are able to draw the Extinction Belt into the Kunad Gate before it closes, eliminating it forever.
Suddenly, Karen copies the Red Strings power once more and makes a final jump in time. The Red Strings envelop the world itself and history is rewritten. When the party recover, they notice that everything is largely the same, except for a crucial difference – Alice is alive, and has apparently taken Karen’s place in the world.
A few questions crop up here, which I will attempt to address:
What was Karen’s plan?
Karen’s plan changes a little throughout the game, but is ultimately founded on the same single objective – saving Alice.
As a reminder, Alice was actually Fubuki’s fiancé. She joined the OSF alongside Karen and Fubuki, and it’s clear Karen had strong feelings towards her even if these were not explicitly confessed. On a mission, she pushed Karen away from Other particles and saved him at the cost of metamorphosising herself.
Karen commenced the rebellion against New Himuka and sided with Seiran for two main reasons – New Himuka were experimenting with metamorphosis, which disgusted him, and Seiran were attempting to find a way of undoing it. Since Alice was still alive – living as an Other in Seiran’s research facility – his goal aligned with theirs.
Alice, in Other form, died during Kasane’s story. At this point, Karen realised the only way to save her is to use the Red Strings and travel through time to undo her metamorphosis. It’s not clear why he kept failing with this objective, but he had attempted this time and time again, never being able to prevent Alice’s death.
Another future version of Karen had already travelled to the past and assassinated Yakumo Sumeragi in order to link with Arahabaki whist in cold sleep. This would enable him to absorb the power and information within, enlightening him about the Red Strings and assisting the present-day Karen where needed. I’ll explain this a bit further below.
At the very end of the game, he realised the only way to save Alice was to sacrifice himself, so he travelled back with the Red Strings one more time and somehow erased himself from existence. This did not produce a new entanglement within the Kunad Gate because these disappear when the creator of the entanglement is killed (which happened with Wakana).
Why were there two Karens?
This isn’t expressly explained very much during the final scenes of Scarlet Nexus, so includes a bit of speculation on my part.
Karen, at some point after Alice’s death in a prior timeline, learned of the Red Strings and travelled back in time 2,000 years and replaced Yakumo within Arahabaki, which created a new timeline. The following 2,000 years passed, and eventually present-day Karen was born as before. He joined the OSF, met Alice, and then ended up dabbling with time travel and the Red Strings in this timeline as well.
It’s not clear which exact period of time the Karen who emerges from Arahabaki is from, but it doesn’t really matter – from the point he assassinated Yakumo it created the new timeline that the game takes place in. During the events we witness there were always two Karens alive at the same time, we just didn’t know about one of them. Here’s an effort to simplify:
- Timeline 1 (original) – Karen is not inside Arahabaki; Karen is born; Alice dies; Karen travels back to assassinate Yakumo and occupy Arahabaki
- Timeline 2 (the timeline experienced during the game) – Karen travels back from timeline 1 and occupies Arahabaki for 2,000 years; Karen is born as usual; Alice dies as usual; Karen repeatedly time-travels to try and save Alice using Red Strings information fed to him from Karen within Arahabaki
However, it is shown that whilst two people can be alive in the same time period, they cannot meet each other. In Karen’s case this created a paradox where the assassin Karen was absorbed – along with his memories – into the present-day Karen.
How did Alice survive?
Karen failed to save Alice time and time again, before realising the only way to prevent her metamorphosis and death was to sacrifice himself. His entire existence was erased from history, and Alice was alive at the end of the game. In a pretty heartbreaking moment, it transpired she didn’t know Karen at all.
The specifics of what exactly happened to Karen in the past were not explained, but it can be surmised that since Karen didn’t exist in the new timeline, Alice never had to risk her own life to save him.
Somehow, the rest of history remained largely unchanged, which is a little more difficult to get our head around. Somebody else started Karen’s rebellion, and everyone else’s life was apparently unaltered. The only reason the cast of the game was even able to remember Karen was because they had been connected to the Red Strings.
Is Karen actually Yuito’s ancestor?
Yuito puts this question forward during the ending, but it remains unanswered in the following scenes. This is more speculation on my part, but on balance I believe Karen is not Yuito’s ancestor, as it simply doesn’t tie in.
Karen’s motivation was to save Alice, and it makes little sense for him to have fathered children with a different woman whilst back in time. I think it is far more likely Yakumo’s heirs had already been born or at least conceived by the time he was killed.
Also, the fact Yuito still exists during the ending despite Karen’s own existence being erased would suggest he was not a descendant of Karen – though admittedly they could probably get around this with some sort of Red Strings-related explanation.
What happened to Yakumo Sumeragi?
With Karen’s existence erased, he basically refreshed the timeline so he never assassinated Yakumo. It seems the new timeline in place during the ending would have branched off in a different direction from the point Karen would have been born. This begs the question of what actually became of Yakumo.
There is the possibility he is actually still alive but also perhaps not – the Yakumo who entered cold sleep in the timeline of the game was always Karen – Kaito simply didn’t know this. We therefore don’t know if the real Yakumo would have entered the cold sleep. He may simply have died of old age or some other cause, leaving no-one inside Arahabaki.
Will Yuito lose his powers?
It was hinted on many occasions that Yuito would lose his powers due to the fact they were granted artificially. By the end of the game, Yuito himself was comfortable with the idea, and had come to terms with the possibility he may revert to being a dud at some point in the near future.
Perhaps Bandai Namco were simply hedging their bets. If Yuito proves to be popular enough with fans, they could retain him as the playable male lead. After all, future-Yuito retained his powers when Kasane encountered him. If he doesn’t prove as popular, then there’s a story-based explanation to put him on the sidelines and create a new protagonist or simply let Kasane take centre stage on her own. For the record, I hope Yuito sticks around as a playable character in a sequel.
What happens next?
The Scarlet Nexus plot and ending definitely lay the groundwork for a potential sequel, and Kasane’s future plans sound particularly interesting. Whereas Yuito expressed a desire to enter the political sphere – perhaps without his powers – Kasane’s objective was to travel to the moon.
The moon has not been contacted for some 2,000 years, meaning the situation is unknown and likely dangerous. We don’t know if Others ever managed to invade, or if the people of the moon would now be friend or foe – they haven’t exactly been considerate neighbours so far. I’d suggest Kasane’s trip to space is the likeliest premise for a sequel.
On Earth, the party mention there are still Others to destroy, but there is no longer a continuous supply coming from the Extinction Belt, so once they’re beaten, they’re gone forever.
Provided there is enough commercial success, there are plenty of ways Bandai Namco could approach a sequel. It seems pretty clear they expect good things, so time will tell.
Interestingly, if you read the story recap in the menu (which I did several times to write this article!), the final phase contains the following line in both routes, courtesy of Satori the Archivist:
“His/Her story will continue. Or perhaps I should say, this is where it truly begins”
I hope this cleared things up in within the pretty confusing Scarlet Nexus plot. If there are any further observations or questions, please comment below!