Crop Circles

A man is trying to sell a piece of land with a crop circle on it An FBI agent tries to arrest him for this but he gets away He find instead an alien tool which a shape shifting alien steals back Heshe shows the agent the crop circles as a trade for keeping the land A spaceship lands and the agent enters it He finds a decaying alien with an egg on it He gets chased by another alien and kills it only to have it regenerate and kill him The agent is healed by an alien and knows theyll return