Spoiler alert: This article contains spoilers for The Walking Dead Season 11 premiere.

The Season 11 premiere of The Walking Dead starts off with many of our fearless survivors breaking into an old military base to find food and supplies. They manage to leave with a few items (though not nearly enough), but the real kicker is what else they find at Fort Connors: sleeping zombies. Or walkers, as they're known on the show.

This triggered the most important question from the premiere, other than whether or not Maggie is alive: Do zombies sleep in The Walking Dead? This isn't the first time viewers saw walkers in an un-moving state. But until a drop of blood falls on one of the many fallen soldiers in the base, they all appear to be zonked out.

So, do zombies sleep in 'The Walking Dead'?

In other seasons of The Walking Dead, viewers have seen zombies in trance-like states, usually because they've been left alone for long periods of time. In these instances, the walkers were jolted "awake," so to speak, by the sound of a person near them. But they were never really sleeping.

However, the Season 11 premiere sort of changes all of that. When Maggie and the rest of the gang come upon the dead soldiers at the top of the episode, they seem to be asleep. In fact, the only thing that stirs one of them is a drop of blood that falls on its face.

Later in the episode, other walkers in a subway tunnel seem to be asleep until someone unwraps a tarp covering one of their faces.

Although the show never introduced sleeping zombies before now, The Walking Dead comics did. In the comics, the survivors come across what they call "lurkers."

They're zombies, or walkers, who essentially appear asleep or dead because they're starved and lack energy. Of course, the one thing that reinvigorates them is the smell of blood. And in The Walking Dead Season 11 premiere, viewers see that in action.

What caused the zombie outbreak in 'The Walking Dead'?

No one attached to The Walking Dead ever confirmed what caused the zombie outbreak. It's understood early in the series that a virus spreads through the world, infecting hosts and mutating their DNA. Eventually, a member of the CDC tells Rick, the virus is airborne. But it isn't confirmed what caused the virus that leads to the outbreak.

Instead, creator Robert Kirkman remains mum on what he believes caused the outbreak in the comics and the show. In January 2020, according to Den of Geek, he allegedly tweeted at a fan that a "space spore" caused the outbreak. But he deleted the supposed tweet and no other explanation was given.

For most fans of The Walking Dead, though, all that matters is that now, zombies can apparently sleep. And that's pretty wild.

Watch The Walking Dead on Sundays at 9 p.m. EST on AMC.