Currently Being ModeratedNov 9, 2012 3:59 PM (in response to dannymaca)
Unless you saved the project it will have become corrupted by that sudden shut-down.
You may need to re-create the project.
But first try this:
Close iMovie. Go to to Home/Library/Preferences and delete the file com.apple.iMovie.plist
Restart iMovie and reset all your preferences, then try opening that project again.