There will no doubt be Walking Dead fans who assume the powers that be killed off both Lori and T-Dog Sunday night in a move to free the show of both its most maddening and most useless character in one fell swoop. And maybe there’s some truth to that. Lord knows we could have saved ourselves a lot of eye-rolling had both been done away with earlier. But I think the two deaths are more a facet of — and exclamation point on — exec producer Glen Mazzara’s new mission statement for the show, which is to keep it moving forward, always forward, at breakneck pace with little regard for what was considered important in the show’s past. Like, say, Rick and Lori’s marriage. I know I expected multiple episodes devoted to the two making peace with each other building up to the birth of their baby. But, nope, that little end-of-episode conversation from “Sick,” along with a brief wave of acknowledgement between the two in this episode, is all the relationship patch-up we got before Maggie was forced to deliver Lori’s child by C-Section, costing Lori her life.

The relentless forward momentum is currently something The Walking Dead shares with Showtime’s Homeland, which also airs Sunday nights immediately after Dead wraps up. Now, I’m not saying the quality is the same; The Walking Dead is much improved this season, but not that improved. But, together, these two shows are racing through plotlines right now at a speed that makes the rest of TV look like it’s moving in slow motion. They are shows with a purpose. And that’s the thing: If a show has purpose, it’s easier to forgive it its faults.

And “Killer Within” has faults. For most of its running time, the episode deals with all hell breaking loose after the prisoner that Rick left for dead two episodes back returns to let a pack of walkers through the fences into … well, into places where zombies aren’t supposed to be. Truth is, it’s all a bit confusing. A lot of that has to do with the fact that show has spent very little time explaining the intricacies of the prison’s layout past that there are multiple cell blocks that can be locked off from each other. So, in an episode like this one, when the group gets torn apart into several smaller groups, and those groups are constantly moving through gated fences and from outside to inside, it gets incredibly tricky to keep tabs on who’s where. Then there’s the matter of Carol. Honestly, I’m not sure if she’s supposed to be dead or alive … or if the show just doesn’t want us to know yet. On first viewing, I thought it was clear that she made it through the dangerous section of whatever cell block she was in thanks to T-Dog’s heroics. But then, at the end, when Daryl says Carol didn’t make it, I rewound the episode and saw that he indeed picks up that head-scarf thing Carol was wearing from next to a ripped apart body, which I originally guessed was T-Dog’s. But maybe it was Carol’s? I assume this will be cleared up next week, but it’s an odd loose thread for an episode that didn’t leave much else hanging.

And there was more that bothered me about this ep: Walkers appearing from nowhere in prison areas that were seemingly wide open. Michonne practically accusing The Governor of murder right to his face with nary another soul in sight. (Not bright, Michonne. Not bright at all.) The Governor so quickly giving up his real name to Andrea after his chilling refusal to do so last week. In fact, I thought the entirety of the Governor’s storyline was a big stall this week, with basically no new information revealed about the man or his plans. Added up, these minor criticisms likely make this my least favorite episode of the season thus far, but, ultimately, it’s tough to go too hard on a show that has grown a massive set of balls since last year and isn’t afraid to show them. I feel like if this were season two, we would have gotten a long, drawn-out episode dedicated to T-Dog’s death, even though he’s a character no one gives a damn about. But since this is a series reborn in season three, T-Dog is given his proper due by having his demise serve as merely an undercard to greater tragedies to come. Good. It’s all that guy deserves.

Writer Guy Ferland and director Angela Kang had the tough task of making Lori’s death an emotional event, even as some folks watching at home were probably celebrating the development. For the most part, they succeeded. I particularly liked how the show cut back to Rick’s “no more kid’s stuff” speech to Carl from season two when it became clear that Lori wasn’t going to make it and that Carl was going to have to put a bullet in her head to make sure she didn’t come back as a walker. That helped fill the hole that results from Chandler Riggs not being a particularly talented child actor. Sarah Wayne Callies, however, acquitted herself nicely in her final scene. Turns out she can be a sympathetic character with the right material!

Another thing about TV shows that move as quickly as this one is right now: As thrilling as they can be to watch, it doesn’t take much for them to run off the rails. The Walking Dead is now shaving off characters to go with its renewed focus, but at some point, it’s going to have to give us real reasons to care about the ones who remain. The writing staff will need to choose those reasons carefully. When Rick’s group and the Governor’s group do collide, the writers will want us to be firmly in Rick’s corner. If we’re not — if we’re just there to watch the mayhem and aren’t too interested in picking a side — that would be a huge failure. But in the meantime, I’ll keep on enjoying having no idea what crazy-ass, show-reconfiguring shit is going to go down next.

A few more thoughts on “Killer Within” …

– T-Dog’s end must be the most welcome TV death since Nikki and Paulo on Lost. I think I actually exhaled a sigh of relief when he got bit.

– Michael Rooker was again awesome this episode and is benefited so much by Mazzara running this show now instead of Frank Darabont, who so often falls back on writing walking stereotypes instead of characters. Loved his delivery of: “How come we never hooked up?” to Andrea.

– Shut up with your stupid hashtags, Chris Hardwick!

– The ep’s best zombie kill: Glenn slicing a walker’s head in half horizontally with a machete.

Follow Bob on Twitter: @robertbtaylor