"Regeneration" is the forty-ninth episode of the American science fiction television series Star Trek: Enterprise, the twenty-third episode of the second season. It first aired on May 7, 2003, on the UPN in the United States. The episode was written by Mike Sussman and Phyllis Strong, and was directed by David Livingston. It was a follow-up to the feature film Star Trek: First Contact. Set in the 22nd century, the series follows the adventures of the first Starfleet starship Enterprise, registration NX-01. In this episode, a research team in the Arctic inadvertently triggers the reanimation of several cybernetically enhanced aliens, killed in apparent spacecraft crash over a hundred years earlier. The aliens assimilate the researchers before escaping into space. The Enterprise pursues the ship and is attacked, forcing Archer to destroy the vessel. Afterwards they discover that the aliens sent a message into the Delta Quadrant containing the coordinates of Earth, a message that will not arrive until the 24th century. The episode used props and costumes from previous Star Trek series in order to represent the Borg. The guest cast included Bonita Friedericy, the wife of main cast member John Billingsley. The ratings received by the episode were similar to those received during the previous week, and the number of viewers were one of the highest for the year. The critical response to "Regeneration" was mixed, with concerns directed at potential continuity problems, and that the appearance of the Borg was a little obvious. A follow-up episode to "Regeneration" was pitched for the fifth season of Star Trek: Enterprise but the show was cancelled at the end of the fourth season. Plot A team of researchers discover remains of a crashed spaceship in the Arctic Circle, finding two humanoids with cybernetic implants frozen in the wreckage. The bodies are taken to a nearby compound to be studied. The scientists marvel at the nanoprobes that begin to repair the long dead aliens. One of the seemingly dead subjects attacks the scientists, assimilating them. Using scavenged parts from the wreckage of the Borg ship to enhance the transport, they escape into space, upgrading it with a faster warp drive and weapons. Admiral Forrest orders Enterprise to rescue the "kidnapped" researchers. They soon receive a distress call from a Tarkalean freighter, and they arrive to discover the ship under attack from the enhanced transport. Captain Jonathan Archer tries to disable their weapons,