When I was very young, I saw a movie where an egg is left on a nun's doorstep and a baby hatches from it. The nun raises it and the girl grows up. When she grows up, two freaky-looking guys grab her and say, "We're taking you back to where you belong."
That's all I can recall, but if anyone had any ideas on what the movie might be, please let me know. This is the best I could string together of the few things I saw. It's been getting at me for years!