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 planet's been at total war 
against the BETA for 30 years,
،كان هذا الكوكب في حرب كليّة ضدّ البيتا لثلاثين عامًا
Este planeta lleva 30 años en guerra
contra los BETA
Este planeta lleva 30 años en guerra
contra los BETA
Cette Terre est en guerre contre eux
depuis trente ans.
L'intero pianeta è in guerra totale 
contro i BETA da 30 anni
Este planeta está em guerra total
contra o BETA há 30 anos,
Этот мир больше тридцати лет назад погряз
 в полномасштабной войне с БЕТА.