"This is about the fifth time this morning-- at not yet 8:30-- that a truck has gone by laden with dirt. A big truck. This also went on all day yesterday.
Now, a couple of things make this mysterious: we live on a cul-de-sac, so they're not going through our streets to someplace else; and all the lots on these 2 streets already have houses on them.
So I've decided that someone watched LOTR too many times, and has decided to bury their house to make it more like a hobbit-hole. It's the only rational explanation."