Bring a flashlight.  Or a headlamp, if you have one.  Bring a sweater, no matter what the weather is like outside.  The further we go, the cooler and darker it will get.  Bring boots too, the higher the better.  The walls and ceilings drip and ooze, the floors are wet with muck.  Down there, under the city.  Down in that... wilderness?  Well, it may be uncultivated and inhospitable, but it certainly is inhabited.  What inhabits it depends on how deep you go.  In this episode we’ll go as deep as we can.  Deeper than perhaps we should.