From the introduction: You've seen strange and interesting worlds in your travels, so when you arrive, you're at first confused, then scared. It seems like, against all odds, you're back home. But, then you notice an insignia on the wall of a nearby building, a circle with three arrows, equidistant from each other, pointing through it towards the center, with an exaggerated outline drawn around it. Underneath is written, "Secure. Contain. Protect." You grit your teeth and suck in a breath; it's going to be a wild ride...