The aliens

they never were destroyed

they took a portal that, for some reason, has a side effect of casting some red light on different astral bodies, including the moon; hence the expression "blood moon". In these times, things often go crazy down on Earth. Hormonal deregulation that no doctor can explain. Demographic changes. People taking crazy and dangerous decisions. Nobody really notices, because everyone is affected.

What if the aliens came back as the moon is turning red again??