Who is Watching Whom

There are three invisible shadows
I cannot see the monsters
I cannot see their shadows
What if they find out
A dog is barking
A candle burns in a pumpkin
On the porch across the street
The empty lot beside it
The empty lot beside it
Someone is tying a string to a pole
The wind blows it out of his hand
Into the monster's face
I cannot see their shadows
What if they find out.