'The Walking Dead' Premiere Fixes One Of Its Oldest Plot Holes

As the countdown to the final days of Rick Grimes begins, “The Walking Dead” is finally cooking with gas.

A lot happened in the Season 9 premiere, which aired Sunday: Our ragtag group of survivors rummaged through Washington, D.C. for supplies. Ezekiel (Khary Payton) proposed to Carol (Melissa McBride), who seems into it but like not super into it. Maggie (Lauren Cohan) hanged Gregory (Xander Berkeley) after he initiated a plot to kill her, which seemed to upset Michonne (Danai Gurira) and Rick (Andrew Lincoln). (Because think of the children!)

Amid all the action, though, the show did something a little more subtle. It’s taken nine seasons, but “The Walking Dead” finally addressed one of the biggest plot holes in the show: the magical, never-ending supply of gasoline.

A few weeks ago, I noted in a story that every car in “The Walking Dead” universe seems to appear equipped with a full tank of fuel. Where is all this gas coming from? And why hasn’t it gone bad? Did everyone seriously fill up their tanks and load up on fuel stabilizer supplies right before the zombies showed up?

Well, in the opening shots of the premiere episode, the writers addressed my long-standing gripe. Fans learned this week that the crops over at the Saviors’ sanctuary are dying and as a result, the characters are turning their dead corn into ethanol. We saw barrels of the fermenting stuff on Sunday, which Eugene seems busy concocting. Meanwhile, Daryl had motorcycles seemingly being converted to better use the fuel.

It’s an easy explanation moving forward for the world’s never-ending supply of fuel, and the show glossed right over it. But it had me like:

In fact, I got on the phone with an ethanol expert, professor Harvey Blanch from the department of chemical and biomolecular engineering at the University of California-Berkeley, to see if I could officially put this particular plot-hole consideration to rest.

“The answer is yes,” he told me. “This turns out to be one of the projects the Department of Energy has funded for years, which is how to convert cellulosic material like corn stalks and corn husks, the leaves and so on, and break them down either by acid or enzymes into sugars, glucose and then ferment that glucose into ethanol. So it’s absolutely feasible.”

“You could certainly run cars on that,” he added. “That’s what Henry Ford did in the 1920s.”

OK, I’m onboard. I can accept that Eugene, who miraculously understands anything remotely scientific, is able to make ethanol. The only issue I have now is: do the Saviors have enough corn?

Blanch told me you could conceivably get between 60 and 70 gallons of ethanol from a ton of corn, though it doesn’t really look like the Saviors have that much. The episode on Sunday showed small plots of crops around the Sanctuary, but at this point, I’m willing to give AMC a break. Plus, the Saviors could easily just take the last bit of the endless magic fuel and run out to get corn from somewhere else if they needed to.

As a final note, Blanch weighed in on whether he thought survivors of the zombie apocalypse would be able to kickstart the kind of enterprise ethanol production would entail. “You could certainly do it,” he said, but it would require a sophisticated knowledge of the process ― and it’d be expensive as heck.

“It’s not terribly economic today, but I guess in the event of a zombie apocalypse money doesn’t mean much,” he qualified.

When it comes to fixing plot holes for Rick’s final season, AMC is sparing no expense.

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Maggie (Lauren Cohan)

Three chomps As was the case with Glenn, her captivity also revealed her toughness, and even if she gave up the location of Rick's group, she didn't let the Governor get to her, despite his sick attempts to break her spirit. Maggie may not be the show's most well-defined character, but at least I can remember her name, which isn't the case with her indistinct sister.

Carl (Chandler Riggs)

Four chomps The character who inspired the hilarious Get Out of Here, Carl! has come the furthest; he displayed epic pre-teen badassery by calmly locking down those newcomers and dispatching yet more walkers with smooth, collected ease. All season long, actor Chandler Riggs has been giving an excellent, subtle performance (his work in the episode in which Lori died deserves special praise). All told, we trust this kid to take care of post-apocalyptic business. Carl, can you go toughen up those teenagers on "Revolution" now?

Michonne (Danai Gurira)

Three chomps She's been a compelling addition to the cast, but now that we've gotten to know the taciturn badass, the show's got to make us care about her. She's got to do more than let her sword do the talking for her and give the other survivors at least moderately compelling reasons to trust her. No matter what, though, she's the ultimate weapon in this zombie apocalypse -- do not get on her bad side.

Andrea (Laurie Holden)

One-and-a-half chomps The show made an enormous mistake by continually showing the audience how evil the Governor was and not having the formerly savvy Andrea catch on to any of that. It's certainly not actress Laurie Holden's fault that "The Walking Dead" turned her tough, level-headed character into such an oblivious chump, but it's a problem for the show's future. Job 1 from here on out is undoing the damage done by the boring, passive, clueless Andrea we saw in the first half of the season.

Glenn (Steven Yeun)

Four chomps Ever thought we'd be saying, "Whoa, Carl and Glenn are so badass"? Me neither. As if Glenn's destruction of a walker while chair-bound wasn't awesome enough, the way he created weapons for himself and Maggie from the bones of his undead victim was insane (in a jaw-droppingly good way). For a while there, a lot of us wondered how these folks had survived, but Season 3 has done a fine job of showing how tough they are. You've come a long way, Glenn.

Daryl (Norman Reedus) and Merle (Michael Rooker)

Three chomps These two brothers have stayed pretty consistent -- Merle is still a tough hombre with a taste for vengeance and Daryl is a hard-boiled survivor who still has some shreds of compassion left. Both are solid characters, even if Merle tends to be a bit of a cartoon at times, and their brother-versus-brother throwdown promises to be a whole lot of fun.

The Governor (David Morrissey)

Two chomps I have to be honest: I wanted the Governor to take command of this show, and David Morrissey has been capable in the role, but overall the character is a less charismatic figure than I'd hoped. Morrissey's wandering accent is a distraction, his sentimental attachment to his daughter is offset by those grisly heads, and this may be a nitpick, but I lost some respect for the Governor when he said he'd let the prison re-fill with walkers. Why not use it as a satellite settlement (or his own prison/lab)? In any event, I haven't necessarily disliked the Governor, but he's been less compelling than he could have been. Let's hope he's more memorable when the show returns.

Lori (Sarah Wayne Callies)

Three chomps Still dead, which is good, but I had to once again (as I did in this review) pay respect to Sarah Wayne Callies' bravura exit and credit "The Walking Dead" with setting up a painful emotional path for Carl and Rick. Suffering is what this show is ultimately about, and that should make for good drama as her menfolk work through their grief and try to raise a baby in that brutal world. As long as the show remains more suspenseful than bleak, that is.

Rick (Andrew Lincoln)

Three chomps Andrew Lincoln has done some fine work this season as a more take-charge Rick; he's not just a credible leader, he's a more humane and loyal alternative to the Governor, who tossed Merle aside without a second thought when it suited his nefarious purposes. Whatever flaws he has as a man and a leader, Rick would never throw a member of his group under the bus full of zombies, which is why we root for the Grimes bunch even as their circumstances get more and more desperate.

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