iMovie project won't open

I finalized an iMovie project then put it onto the Desktop, but now it's not in iMovie anymore. When I try to open it from the Desktop (either by selecting "Open with" then "iMovie (Default)," or by just selecting "Open"), iMovie pops up but doesn't show the project. I tried restarting my computer, even though I'm sure there's not logic behind that. Please try to help me get the project back!