In the first part, the human fleet discovers the abandoned planet Kobol. A survey team is stranded there by Cylons while President Laura Roslin convinces Starbuck to disobey orders and retrieve the Arrow of Apollo. In the second part, Commander William Adama stages a military coup and places Roslin in Galactica's brig. Starbuck retrieves the Arrow and discovers that Boomer, still on Galactica, is a Cylon. This Boomer destroys the Cylon Basestar orbiting Kobol, returns to Galactica, and shoots Commander Adama; the season ends on a cliffhanger.

"Kobol's Last Gleaming" underwent numerous substantial rewrites. It was one of the most expensive episodes of the first season to produce. The episode received favorable critical review. Michael Hickerson of Slice of SciFi ranked it as the fourth best episode of the re-imagined Battlestar Galactica. Simon Brew of Den of Geek called it "just outstanding television."

When a habitable planet is found, President Roslin concludes that the planet is Kobol, the mythical birthplace of humanity. Commander Adama wants to begin permanent settlement of Kobol, but Roslin cites scriptures in her belief that Kobol will point the way to Earth. However, this would require retrieving an artifact called the Arrow of Apollo from Caprica; Adama is unwilling to commit vital military resources (particularly the captured Cylon Raider that can make long jumps) when he doesn't believe Earth even exists. Roslin convinces Starbuck to disobey her orders and take the captured Raider to Caprica to retrieve the Arrow of Apollo.

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