Who are they?

Two unknowns show up to the hidden leaf. Knocked unconscious the Hokage, Hiruzen Sarutobi, decides to bring them both in for he senses great power inside the both of them . He decides to enroll the both of them inside konohagakure's ninja academy to possibly bring forth a new coming of ninja and hopes these two will be great assets to the leaf village. The question is.... Who are they? Where did they come from? and will they remain loyal?