Retrieving iMovie 09 Projects from an External Hard Drive

I recently moved some older iMovie 09 projects off my internal hard drive to an external hard drive. While it unlikely that I would ever wish to edit any of these projects, I would like to know that I have the option to do so.

How do I restore a project currently saved on my external hard drive, back to the iMovie application. I moved these projects initially to the external drive using the iMovie program.