Natural born killers?: Carl and Rick Grimes. (Gene Page)

“We’re not broken. We’re going to prove him wrong.”

Those were the words Rick Grimes (Andrew Lincoln) spoke at the beginning of this episode of “Walking Dead” during his eulogy for the dearly departed Dale Horvath. It was Rick’s big “Live together, die alone” moment, his opportunity to step up, prove his leadership skills and unite the group.

Less than an hour later, his words were proven false. Rick and his posse of dysfunctional, perpetually bickering zombie-pocalypse survivors are still as cracked and fractured as ever. And as a result, another key character is dead.

Warning: spoilers ahead. (But really, not that spoilery since I think we all pretty much knew this person was going to bite it this season.)

Shane Walsh, you magnificent, stubborn, Otis-killing, Lori Grimes-obsessed, pseudo-bald bastard — you had to go and get stabbed and then shot by the Grimes boys, didn’t you?

You had to because the “Walking Dead” writers promised major developments in this season’s final episodes, and major developments in a show about a horrifying dystopian society usually mean casualties. You had to because Lori Grimes made that speech about how much she appreciated what you had done for her, which was the first red flag that you were so not going to live through this episode. You had to because Jon Bernthal, the actor who plays you, has signed on to Frank Darabont’s upcoming pilot, “L.A. Noir,” which was kind of a clue that Shane might not survive to hook up with Andrea another day.

Still, it’s a little sad. Shane stood out as perhaps the most compelling conflicted character in season two. It was never clear what Shane might do next, and on a show where everyone has had the same argument at least five times, a dose of unpredictability was welcome.

Naturally, the circumstances surrounding Shane’s death — which occurred after Shane got rid of Randall and involved a stabbing, a zombie-fication and a shooting committed by a preteen — have raised some questions, as did a few other things in this episode. Let’s address some of those now, with further conversation to follow in the comments section.

Shane (Jon Bernthal) (Gene Page/AMC)

Why did Shane turn into a zombie?

This was definitely confusing. I watched the ending three times to try to figure this out and I’m still flummoxed.

After Rick stabbed Shane, there were quick flashes of zombies growling and feasting on something. But we never saw Shane get attacked. It appeared that Rick was standing over his body the whole time, and that the walkers didn’t approach en masse until after Shane turned.

So when and how did this happen? Did Shane have traces of the infection in his bloodstream that were activated once he died? If so, that flies in the face of zombie rules and regulations as we know them. Is it possible Rick was in some sort of trance and that Shane was bitten during that time, while Rick remained unscathed? Because that makes no sense at all.

I am eager to hear theories on this one because honestly, I’m stumped.

Update: As many smart commenters below have noted, it seems fair to assume that the virus that causes zombie-fication is indeed airborn and was already in Shane’s bloodstream when Rick stabbed him. (I failed to note that Randall also zombiefied after Shane broke his neck, another clue that the walkers-must-be-bitten-to-become-walkers rule is actually off the mark.)

The “Walking Dead” writers have not explicitly explained the details yet, but that basic premise — that everyone is already infected — makes sense. And it raises the stakes enormously if anyone who dies immediately adds to the walker population. Thank to all the readers who astutely processed all this. (Also — hey, Andrea, let’s not enable anyone else’s suicidal tendencies anymore, um-kay?)

What was Shane’s plan — did he want to kill Rick or force Rick to kill him?

Shane was clearly goading his old buddy with some highly charged language during their stand-off. (“Lori and Carl, they’ll get over you. They’ve done it before” — I mean, that was cold. Like, buried-in-the-back-of-the-freezer cold.)

But if he had genuinely wanted Rick dead, he could have offed him quickly and easily, the same way he did Randall. Maybe Shane couldn’t muster the courage to kill his friend so quickly. Or maybe Shane just wanted Rick to kill him and put him out of his own guilt and misery, so he was trying to fire him up to commit the act. Personally, I am leaning toward the former — he wanted to blast Rick in the back of the head before he knew where the bullet came from, but doing so was just too hard.

Who is really responsible for killing Shane?

Technically, it was Rick since he stabbed first. But Carl shot Shane in the head after he turned walker, something he might not have done if both his father and Shane hadn’t encouraged him to hold on to Daryl’s gun. So really, this was a joint effort. Not sure how that would be explained in a court of law. (It’s not double murder since only one person died ... so maybe it’s murder to the second power?) Fortunately, since the “Walking Deaders” are living in a time of total anarchy, there probably won’t be a criminal trial in this matter.

Should we assume now that Rick’s transformation into Shane is essentially complete?

I believe so, given the fact that he killed his best friend in cold blood. (Yes, he screamed and cried and felt bad, but that doesn’t change it.). Plus, he gave his son what qualifies as the harshest father-son pep talk in TV history. “People are going to die,” he told Carl. “I’m going to die. Your mom — there’s no way you can ever be ready for it … the best we can do is avoid it as long as we can.” (This, by the way, is the exact same speech Howard Cunningham gave to Richie Cunningham in the rarely seen zombie episode of “Happy Days.”)

Rick’s better angels, to borrow the title of the episode, have become ruthless realists.

Why didn’t Rick and Carl see the thousands upon thousands of zombies heading toward them at the end of the episode?

In the last shot, an upward pan revealed that literally every zombie in the state of Georgia, as well as several from the Carolinas, are heading toward the farm. They were feet away from the Grimes guys. But they didn’t seem to realize how much potential they had to become walker meat in approximately, oh, ten seconds. How is this possible? Can this be explained by using the same flawed logic that presumably explains Shane’s zombieness?

Did Lori Grimes know Shane was going to die?

Per the conversation she had previously with Shane, it sure seemed like she thought it would be wise to have a “final talk.” But I don’t think she knew a stand-off was imminent. I do think she may have had a premonition that her former lover wasn’t long for this world. We women tend to have sixth senses about these things. Although you’d think her psychic powers would help her keep better tabs on her kid’s whereabouts.

Speaking of which, did anyone else laugh out loud earlier in the episode, when Shane asked Carl: ‘What are you doing wandering around by yourself?’

I was so hoping Carl would say, “I’m doing what I do in every single episode. Seriously, don’t you pay any attention to how negligent my parents are?”

This has nothing to do with Shane, but: Wasn’t it nice to see T-Dogg actually doing something (sort of) in this episode?

They finally gave him lines and everything! He even got to make a nice, subtle reference to the Governor, a character who shall rear his head in season three. Truly a banner week for T-Dogg.

Do you think Shane’s demise is good or bad for the future of ‘Walking Dead’?

Well, the narrative in the comic moved ahead just fine after Shane’s death. And there was only so long the writers could drag out the triangular situation between him, Lori and Rick. Plus presumably, Rick is going to go to even darker places after offing his friend, which could be interesting.

But as noted earlier, Shane’s starkly black and white approach to handling life’s major obstacles will be profoundly missed. From now on, we’ll just have to watch “Walking Dead” while always asking ourselves WWSWD — What would Shane Walsh do?