One of the things I love about BSG is how secondary characters develop to become a key in the plot. So Aaron Kelly, former LSO in Galactica, became that key last episode.
The last time we saw him, he was caught taking out members of Baltar’s legal council. So his hatred for Cylon was well established. So during the coup, Kelly was sprung from the brig by Zarek, who knows a little something about domestic terrorism. So for Kelly, the motive is revenge against Cylons and their “collaborators”. And as a former high-ranking officer, Kelly was given a lot of responsibilities, including capturing Adama and Tigh and escorting Zarek.
Despite spending time in the brig, Kelly remains a loyal son of the colonies, committing the bombings of Baltar’s legal council on the conviction that Balter is a traitor. So when he witnesses the massacre of the Quorum under the order of Zarek, he begins to waver.
Then he completely turns when he catches Tyrol crawling around Galactica like a sewer rat. Tyrol delivers what I thought was the best line of the episode.
That’s right, I’m a machine. But what does that make you? Dumbass?
So here is Kelly staring at the “enemy”, someone who is too tired to avoid getting shot. Someone who didn’t even know his wife screwed around. In contrast, he is pledging loyalty to Zarek, someone who just destroyed most of the civilian government. This is not the first time a character had to go through this perception warping trial. Way back in season one, Helo went through the same thing with Athena, discovering that she is as vulnerable and capable of love as any human. The Kelly makes his first key decision, he lets Tyrol go. Tyrol, of course, would go on to shutdown Galactica’s FTL, preventing its escape.
When it was time to assemble Adama’s execution detail, Kelly became part of the escort. He later peels away from that group and went off to his potter’s field and became engulfed with guilt. Fortunately for this Judas, redemption came in the form of Apollo and his group of rescuers. Kelly gives Apollo the admiral’s location and comes with him.
So is this end of Aaron Kelly’s role in the story? Depends on next week’s episode whether how Adama deals with the rest of the mutineers. I highly doubt Kelly will end up the same fate as Gaeta and Zarek, but key characters like Kat do get killed off. I guess the best answer is to stay tuned.