Alexander Robertson Smith & his other siblings were forced to go back to the past, and they were also forced to hide their true identities so ' They ' couldn't being able to find themselves.
Everyone knew that going to the future & going back to the past it's impossible to do, so since Alexander and his siblings didn't have any other choices, they decided to go back to the past.
With a few of their loyal followers, we also come with them. But they also brought their gadgets with them, but they must keep a low profile since they didn't want to attract any attention.
Alexander and his siblings have something that anyone didn't have, that they can see Ayakashi or Youkai, & Akuma (Demon). Every time they went out, and that's where they saw 'Them' (Ayakashi, Youkai, & Akuma). And that makes them feel uncomfortable.
But they also have supernatural, elementals, Vision, Magic / Dark Magic & healing powers. They only used their powers when they wanted to, because they promised that they only used their powers to help others in need.