Season 3, Episode 10:
The fleet's food stocks have become contaminated, forcing Galactica to send out teams to survey for viable sources of food before they run out of food in a week. In a Raptor, Sharon is surveying a gas cloud as a radiation monitor on her shoulder turns from white to black.
While the pilots ration out food, Bill waits to hear back from Sharon about her mission into the cloud. Her Raptor returns, and she is unaffected by the radiation due to her Cylon nature. She reports that she has found a planet that has algae, and Cottle relates that the algae supply will help restock the fleet's food stores.
In a meeting soon after, the crew weighs their options. Bill explains that they can't jump the fleet over normally, as there is no way around the cloud and the radiation would put the civilians on the ships at serious risk. Lee suggests using Raptors to guide groups of civilian ships through the cloud, and place as many civilians on Galactica as they can because the battlestar has hull plating that will abate the radiation.
Bill authorizes the plan, and a schedule is drawn up to bring groups of civilian ships with skeleton crews through the cloud. On Galactica's hangar deck, Kat is walking through when a man with a group of civilians calls out to her using the name Sasha. Kat angrily confronts the man, Enzo, and tells him to stay away before she leaves.
On the Basestar, D'anna wakes up next to Baltar and Caprica-Six in bed, and she gets dressed and leaves. Baltar awakens and asks where D'anna went, and Six tells him that her behaviour is making the Cylons very concerned.
On Galactica, Tigh returns to the bridge and resumes his role as XO to cheers and applause. He tells them that they still have a job to do, and Bill smiles to himself. In the pilot ready room, Lee issues radiation badges to the pilots and tells them that taking stims is optional.
The Raptors ferry several groups of ships through the storm, but two ships are lost. Hot Dog's group loses the Adriatic, while Kat loses sight of another ship, the Carina. She remains in the cloud for several minutes trying to locate it before leaving, but she develops radiation poisoning.
Baltar goes to D'anna and asks her about her activities. He guesses that she has been killing herself over and over again for an unexplained reason, and she confirms it. D'anna then says that she has been seeing five figures wearing white robes, and has been experiencing visions between life and death. Baltar dubs them the "Final Five", and wonders out loud if he could be a Cylon.
D'anna and Baltar go to the Hybrid's chamber to seek any advice, but the Hybrid spouts out more nonsensical phrases. When Baltar gets close and puts out his hand, the Hybrid grabs it and suddenly speaks coherent thoughts to him, saying he should "find the hand that lies in the shadow of light". When D'anna asks him what it means, he says that it could be related to a place where the Eye of Jupiter could be found, and that he now believes that the Hybrid's ramblings are all true.
On Galactica, Kara sees Kat arguing with Enzo and confronts her over the situation. Pressured to come clean, Kat says that her real name is Sasha, and that she was a weapon smuggler before the attack on the Colonies. She says that her full name, Louanne Katraine, was taken from a child who died just before the attack, and she has been using that cover ever since. Kara advises her to come clean to Bill, but Kat says she can do it herself.
Kat notices that her hair is falling out soon afterwards. Motivated to continue the trips, she switches her radiation badge with Helo's and goes out on a run with another group. Once again, a ship, the Faru Sadin, is lost in the storm. Meanwhile, Galactica begins to suffer decompression alerts throughout the ship and makes their final jump to the other side of the cloud. Kat continues searching for the lost ship, knowing that it's already too late for her.
As the CIC crew waits, Kat appears with the last ship. However, when she arrives onboard, she collapses from radiation injuries and is taken to sickbay.
Kara visits her afterwards and tries to make her feel better. Kat says that she knows she's only got a short time to live, and Kara leaves her a bottle of sleeping pills to make things painless. Later, Bill visits her and congratulates her as well. When she tries to admit who she is, he tells her that it doesn't matter, and that it doesn't change the fact that she's a hero. He promotes her to honorary CAG for her deeds, and tells her how he wished he could have had a daughter like her.
In the ready room, the pilots watch as a somber Bill places Kat's name at the top of the pilot chart. In the memorial hall, Kara hangs up Kat's photo and cries.
- The Atoner: Played with. Kat wants to make up for her Dark and Troubled Past, but despite Kara browbeating her over it, Bill tells her it doesn't matter who she was, only what she's done in the present.
- Better to Die than Be Killed: Kara gives Kat a bottle of sleeping pills so she can die peacefully, versus die in agony as a result of the radiation poisoning.
- Continuity Nod: Kara puts Kat's photo on the memorial wall right below the picture of Reilly's girlfriend (which Kat had placed on the wall in "Scar").
- Dark and Troubled Past: Kat's previous work as a drug smuggler.
- A Death in the Limelight: For Kat, who is the focus of the episode.
- Driven to Suicide: While it's implied that she may already have suffered a fatal radiation exposure, Kat knowingly undertakes one last escort mission, partly to make sure that no more ships are lost, and partly because it's implied she can't live with the thought of having her past exposed. Kara's The Reason You Suck speech probably didn't help matters either.
- Due to the Dead: After her death, Kat is symbolically restored to the position of CAG.
- Heroic Sacrifice: Kat deliberately continues her mission past the exposure limit and dies as a result, though she saves several ships in the process.
- He's Back: Tigh, who returns to duty after drinking to alleviate his guilt over the last few episodes.
- Hidden Depths: For Kat, who is revealed to have been a smuggler prior to becoming a pilot for Galactica.
- Incurable Cough of Death: Kat gets it, coupled with sullen eyes and hair loss as a result of her radiation sickness.
- Infinite Supplies:
- Averted; a food shortage forces the fleet to make a dangerous trip through a dangerous route.
- Likewise, Galactica evidently has no anti-radiation supplies onboard, and Kat eventually collapses from exposure.
- It's All My Fault: Kat, as a result of the Carina being lost under her watch.
- Killed Off for Real: Kat.
- Leaning on the Fourth Wall: The Hybrid rambles that "throughout history, the nexus between man and machine has spawned some of the most dramatic, compelling, and entertaining fiction", referencing the show (and the whole sci-fi genre) itself.
- Like A Daughter To Me: Much like his treatment of Kara and (later) Sharon, Bill acknowledges to Kat that he wished he had a daughter like her.
- Pre-Climax Climax: Kat sleeps with Enzo after taking a fatal radiation dose.
- The Prophecy: The Hybrid tells Baltar to find "the hand that lies in the shadow of the light".
- So Proud of You: Bill to Kat, as she lies on her deathbed.
- A Threesome Is Hot: Baltar, D'anna and Caprica-Six on the Basestar.