Last Night.

Last night I decided to go for a midnight wander in the depths of my head. It wasn't long before I came across a group of school children and their teacher all standing next to a river. I was curious and so I stayed to watch. I soon found out that they were having fishing lessons as everyone pulled a fishing rod from their backpacks! Like Mary Poppins' bag it was!
Masses of fish gathered around but nobody caught anything because of a car chase! The cars ran straight down the river from the inside of a nearby cave, the fish scattered and then the cars were gone again. The school kids weren't too happy but I just shrugged it off and left.
I said my head was a strange plaice! Get it? Fish, plaice? I give up...