"A Measure of Salvation" is the seventh episode of the third season from the science fiction television series Battlestar Galactica.
Major Apollo leads a boarding team inside the ship finding most of the Cylons are dead, however a small group is found barely alive on the bridge. The landing team also finds the mysterious cylinder device. Sharon "Athena" Agathon tries to access the Basestar's computer system to no avail. She then speaks with a Cylon copy of herself who calls her a traitor. Apollo requests permission to finish off the Cylons. However, at Captain Helo's suggestion, Admiral Adama orders the prisoners to be brought back to Galactica for interrogation.
Gaius Baltar is confronted by Number Three and Number Six, who ask why he didn't reveal the existence of the device he found on the Basestar. Baltar feigns ignorance at first, but then confesses that he did know about the device, and apologizes for not mentioning it sooner. Three and Six believe that he knows more about the device than he's letting on. They have two Centurions take him away for interrogation.
The Cylon prisoners, including Apollo's boarding party, are placed under quarantine by Doctor Cottle. Later, he determines the virus to be a strain of Lymphocytic Encephalitis, one that has caused the Cylon's brains to swell and other symptoms like high fever, stupor and disorientation.
Cottle reports to Adama and President Roslin that he can create a serum that will suppress the virus and keep the Cylons alive, without ever curing them; the Cylons will have to be given periodic injections to keep them alive. A Cylon copy of Simon is brought before Adama and Roslin. In exchange for the serum, Simon explains the Cylons' plans to find Earth. He reveals that Baltar is with the Cylon fleet and is showing them the way to Earth. Simon further explains about the probe, and how the contaminated Basestar was abandoned by the rest of the Cylon fleet.
Apollo realizes that the human race now has a way to exterminate the Cylons once and for all. All they need do is execute their Cylon prisoners within range of a Cylon Resurrection Ship. Captain Helo objects to this plan, arguing that exterminating an entire race would be a "crime against humanity" and make the humans no better than the Cylons. Apollo argues that the Cylons are not human and they should be wiped out. Helo retorts saying that Sharon ("Athena"), his wife and a Galactica officer, has proved her loyalty, risking her neck time and again to help the human survivors and believes there may be more Cylons that think as she does.
Adama meets with Roslin on Colonial One to discuss the proposal to wipe out the Cylons. Roslin is in favor of the plan, but Adama is uneasy, pointing out that he needs a Presidential Order to use biological weapons. Roslin sees through this as Adama's way of "passing the buck", a point that Adama readily concedes. Roslin takes the responsibility, and orders Adama to carry out the plan to destroy the Cylons with the virus.
Baltar continues to be tortured by Number Three who demands he tell her what he knows. Gaius's mind however drifts in and out between the torture room and the beach with Six, who begins to make love to him. In between intense pain and erotic pleasure, Baltar talks of religion and faith, a monologue that makes little sense to Three because Gaius is actually talking to the Six in his head. He tells Six he loves her but Three doesn't realize who he is talking to, and she ends the torture with a look of pity on her face.
Adama tells Roslin that the Cylons were killed before they had a chance to download to the Resurrection Ship, and that the plan to infect the Cylons with the virus has failed. Roslin believes there are only two possible suspects and asks what Adama is going to do about an investigation. Adama believes the device was a marker, and that they are definitely on the right track to finding Earth. Roslin agrees with this, but points out that if the humans are on the right track to Earth, then the Cylons must be too.
James Callis submitted this episode for consideration in the category of "Outstanding Supporting Actor in a Drama Series" on his behalf for the 2007 Emmy Awards.