"Resistance" is the fourth episode of the second season of the reimagined Battlestar Galactica television series. It aired originally on the Sci Fi Channel on August 5, 2005.

In the episode, Marines fire on civilians following Colonel Saul Tigh's declaration of martial law. President Laura Roslin and Lee "Apollo" Adama escape Galactica, Commander William Adama recovers, and Specialist Cally kills Galactica-Boomer. On Caprica, Starbuck and Helo join a human resistance group led by Sam Anders.

When civilian ships protest martial law, acting commander Tigh orders marines to take withheld supplies by force. On the civilian ship Gideon, Marines open fire on a hostile but unarmed crowd of civilians, killing four. Fearing a split in the fleet, President Roslin and Apollo enlist help from Racetrack and Dualla to escape the brig, and go into hiding with Tom Zarek, Roslin's erstwhile political enemy.

Tigh has Chief Galen Tyrol thrown in a cell with Boomer who has recently been found to be a Cylon. He then orders Baltar to determine whether he is also a Cylon. Instead, Baltar injects Tyrol with poison and demands that Boomer reveal the number of Cylon agents still secretly aboard the fleet. After Boomer guesses that there are eight agents, Baltar administers the antidote and later clears Tyrol of being a Cylon.

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