Two masked children approach Mai Sahara and ask for her help — their mother is in pain. She follows them. The path leads to a mountain shrine she has no memory of, in a location she cannot place. The shrine's resident, a being named Imigo, is unwelcoming and sends her away. Something keeps her there regardless. When even Imigo cannot dismiss the force holding Mai in place, he relents and agrees to help her find the way out safely. The journey they begin together gradually draws Mai toward the truth of her own past — something she did not know she had been carrying.