Shirogane Takeru found himself inexplicably transported to a world that resembled his own in many ways, with one major difference: For nearly 30 years, mankind has been at war with the alien BETA, who have succeeded at wiping out over half of humanity and had nearly captured the entire Eurasian continent. As Takeru tried to come to grips with this bizarre new reality, he realized too late that the majority of humanity will be abandoned with the Earth, as the chosen few escape to the stars, hoping to find sanctuary.

Now, equally inexplicable reasons, he finds himself returned to the first day of his time in this alternate world. Will the experiences and knowledge he has gained allow him to make a difference?
This approach is also less dangerous 
than targeting the facility itself,
،كما أنّ هذه الطريقة أقل خطورة من استهداف المنشأة نفسها
Dieser Ansatz ist auch weniger gefährlich
als ein Angriff auf die Einrichtung selbst,
Este enfoque también es menos arriesgado
que atacar la base en sí.
Este enfoque también es menos arriesgado
que atacar la base en sí.
C’est aussi moins dangereux
que de viser directement l’installation,
Questo approccio inoltre è meno pericoloso
 rispetto al colpire la struttura di per sé,
Essa abordagem também é menos perigosa
do que visar a própria instalação.
Также это менее опасно, 
чем проникновение на базу,