You take a couple of steps onwards, and suddenly you find that there's nothing ahead of you to step on. After a few seconds of falling you land hard at the bottom of the pipe. Although the fall has left you winded you don't appear to be hurt, which lends credence to the theory that you're more resilient in this shrunken form.
Amazingly there's a little light in here, shining in through a join in the vertical stretch of pipe you just fell from. Apparently you're in a T join, where the vertical pipe you came out of connected to a horizontal pipe. This gives you two different directions to travel in, both trail off into darkness. Distant noises tell you that one pipe leads towards running water, while the other offers the much more distant sound of a lawnmower running. You can't say for sure where the sounds of running water will take you, but you feel absolutely certain that following the sound of a lawnmower means that you'll wind up in a drainage pipe in your yard.
