An Unexpected House Guest

Recently I noticed that some of my plants look like something was munching on them.  Well, there was a hungry hungry caterpillar living among my window boxes.  He scared the bejeebers out of me when I found him ascending my curtains.  I'm not sure what type of caterpillar this is or how it got into my window boxes which are behind a screen, but he was really big, close to about three inches.  As much as I like wildlife and nature I decided that having him in the apartment wasn't the best idea.  Simon liberated him to the outside world.

Upon looking him up I discovered that this is a yellow stripe army worm.  They turn into a brown moth and the larva can do serious damage to plants.  I only found one so hopefully he is by himself.