Credit: Gene Page/AMC Photo: Karen is Sweaty on The Walking Dead Season 4, Episode 2: “Infected”

The Karen and David killer mystery took a shocking turn on The Walking Dead Season 4 Episdoe 3, "Isolation." But is the truth even more out there than Carol (Melissa McBride) being the culprit?

Rick Grimes (Andrew Lincoln) asked Carol if she killed Karen and David. Her answer was "yes." For some people, that was enough of an admission, and The Powers That Be — including episode writer Robert Kirkman — discussed Carol's decision as if it was entirely her own. But what if they are being extra sneaky and the truth is that Carol is just covering for someone else — like young Lizzie?

It was shocking enough to think Carol did it, but we're (kinda) willing to accept that she's in a place now where she felt like she did what she had to do. To some other fans, Lizzie as the killer/burner makes more sense. Rick found a very small, low handprint on the door that some people think is a better match for Lizzie. Carol swore she'd protect Lizzie, who has already been deemed "weak" by Carol and "messed up" by her own sister Mika. Lizzie was a walker fangirl (see her obsession with "Nick"), but maybe to prove she's becoming stronger she took matters into her own hands.

The promo for this Sunday's Episode 4 (see below) also shows someone dragging a body, and Lizzie telling Carol, "A lot of people are going to die, it always happens." Carol responds, "You don't give up." What if that's a flashback (since Lizzie is supposedly sick and in the separate ward now), showing who killed and dragged the bodies? Maybe it was Lizzie who killed them and Carol did cover it up.

It still doesn't make a ton of sense — This scared little girl killed two sick people and managed to drag their heavy bodies out into the yard to burn them? How did she even know Karen and David were the only sick people? Only the council people knew, so did someone tell her? — but accepting Carol as the killer takes some logic stretches too.

Some people also think Karen and David may have already been dead and Carol/Lizzie just dragged and burned their bodies. The assumption from everyone in the prison is that they were killed “in cold blood,” not just put down when they were already dead. People put down the dead all the time and it’s not considered killing, so we have to accept the in-show mindset that this person took lives as a preventative measure.

Maybe Lizzie killed them and Carol dragged and burned them as part of the cover-up? It still seems convoluted, but… To some viewers, the act of killing and burning people on the sly was so un-Carol-like that there had to be a different, more selfless explanation — like covering for troubled Lizzie. Even ushering Lizzie into the sick ward might be seen as a way to keep the girl safely away from anyone else.

Unless/until The Powers That Be spell it out in plain words — "No, people, Carol WAS the killer" — there will probably be speculation that she was just protecting her new Sophia. What do you think? Tell us below!

The Walking Dead airs Sunday nights at 9 p.m. ET on AMC.