Im searching the name of movie in the 80,90s about alien and farmer. The only thing a remember is the alien kidnapped the men (the farmer) and he was in some liquid similar like a uterus or placenta (alien do experimental thing on the humain) inside the spaceship. And after that, he come back on earth but he wasn't the same as before...

Perhaps Fire in the Sky (http://en.wikipedia.org/wiki/Fire_in_the_Sky)?

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It was definitely Fire in the Sky