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Kara "Starbuck" Thrace and Karl "Helo" Agathon encounter the Caprica resistance, who initially believe the two are humanoid Cylons (due to the copy of Cavil that's a "member" of the resistance) before Thrace and Agathon manage to convince them otherwise.
The resistance cell that Agathon and Thrace encounter is led by Samuel Anders, a former professional Pyramid player. Anders and several other members of his team, the Caprica Buccaneers, were in the high mountains well outside the city at the time of the Cylon attack. After the initial attack they formed a resistance movement centered around their pyramid team, supplemented by hikers and other survivalists who had remained alive in the mountains when the Cylons hit. They have survived by raiding old military stores for munitions and other supplies, including anti-radiation medication. They conduct guerrilla attacks against the Cylons in an attempt to keep the enemy forces off balance and, hopefully, to force them to leave their colony.
The resistance leads an assault against a Cylon-operated farm where Kara Thrace and Sue-Shaun are incarcerated. Thrace escapes on her own power, but finds Sue-Shaun already connected to the Cylon devices intended to harvest her ovums or impregnate her. Thrace mercy-kills Sue-Shaun on her request.
As Thrace leaves the building, she encounters another copy of Simon, having killed a copy moments before. The resistance team eliminate this copy quickly, but are soon pinned down by Centurion gunfire before renegade Cylon "Caprica Valerii" obliterates the Cylons from a stolen Heavy Raider and evacuates the humans from the area.
Anders hides Kara Thrace's Arrow of Apollo on the high school grounds and returns it to her before she, Valerii, and Agathon escape the planet and return to Laura Roslin and her faction above Kobol (The Farm).
A copy of Cavil infiltrated the resistance (Lay Down Your Burdens, Part II, No Exit) but was executed by being blown out Galactica's airlock with another copy of himself when his true nature was discovered. Unknown to the resistance, his time among them caused him to change his perspective and mind about humanity, coming to believe that what the Cylons did was wrong. As a result of this, he was presumably boxed once he resurrected (The Plan).
The resistance is also unaware that their doctor, Simon, is a Cylon agent until they rescue Thrace from a Cylon Farm. The resistance members kill a Simon outside the farm and seeing his corpse causes them to realize that their doctor is a Cylon and Barolay is sent back to execute him. A deleted scene reveals that the Simon was killed, but not before he contaminated their anti-radiation meds (The Plan).
The resistance finds its numbers heavily weakened after a Cylon attack, months after Thrace leaves their party. Fortunately, a massive Search-and-Rescue effort, led by Thrace, returns to find Anders and the remnants of his team. After the group's ambush by Cylon forces (who have left for good, according to the copy of Cavil), Anders' resistance team boards the SAR Raptors and leave Caprica for the Fleet (Lay Down Your Burdens, Part II).