"Home Soil" is the 18th episode of the American science fiction television series Star Trek: The Next Generation. It first aired in broadcast syndication on February 22, 1988. Robert Sabaroff, Karl Geurs and Ralph Sanchez developed the story, with Sabaroff producing the teleplay. "Home Soil" is one of five episodes of the series directed by Corey Allen.

Set in the 24th century, the series follows the adventures of the Starfleet crew on the Federation starship Enterprise-D. In the episode, the crew of the Enterprise investigates the murder of a crewman on a terraforming colony and discover a crystalline life form possessing intelligence.

The production team encountered problems with the sets, casting, and scheduling. Due to issues with the script, it was delivered to Allen just one day before shooting. Nine million viewers watched the episode, the second lowest number of viewers for the first season of The Next Generation. Critical reception was mixed, with one reviewer noting that unlike the original Star Trek series, "Home Soil" explored the realm of hard science fiction. Critics compared the appearance of inorganic life forms in the story to the plot of the original Star Trek series episode, The Devil in the Dark.

The Enterprise arrives at the terraforming colony on Velara III, as the project is behind schedule. The director, Kurt Mandl (Walter Gotell), insists they are on time but Captain Jean-Luc Picard (Patrick Stewart) orders an away team to the surface after Counselor Deanna Troi (Marina Sirtis) senses that Mandl is hiding something. After they arrive, one of Mandl's team is killed by a malfunctioning laser drill. During Lt. Commander Data's (Brent Spiner) inspection of the tool, it begins to fire at him, but his quick android reflexes allow him to dodge the shot and render the drill harmless. He finds the programming of the laser was rewritten to fire upon the staff. Nearby, a crystal is discovered giving off irregular light and radiation patterns. The crystal is brought aboard the Enterprise to study and Picard orders a halt to the terraforming.

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