'Silo' Season 3, episode 1: That weird cloud and goo, explained

We're back for another season of Silo, but this time we're spending just as much time outside as we are in.

Season 3 picks up where Season 2 left off, making it clear that the shocking flashback in last season's finale wasn't just a one-off. Alongside Juliette (Rebecca Ferguson) grappling with memory loss in the present day, the episode also follows congressman Daniel Keene (Ashley Zukerman) and journalist Helen Drew (Jessica Henwick) in the pre-silo days, with Keene's naval pilot sister Charles (Jessica Brown Findlay) heading off on a combat mission that almost gets her killed.

But what's with the mysterious cloud she encounters, and how might it connect with the silo? Let's dive in.

What happens in Silo Season 3, episode 1?

After a peculiar meeting in which she warns her brother to get on the Iran committee run by Senator Thurman (Laura Innes), we see Charles cutting through the clear night sky on a mission with her fellow naval pilots.

All seems to be going well until a weird cloud appears up ahead. It looks almost like a storm cloud, only with long dark tendrils creeping out of it. "What the fuck's a cloud doing at fifty thousand feet?" asks Charles as she and her fellow pilots fly into it.

Inside the cloud a weird, gooey substance shows up on Charles' instrument panel. She touches it, and the residue is reminiscent of the tendrils we saw protruding from the cloud. Shortly after that, planes start to go down around her.

Watching news of an Iran combat mission on TV, Daniel Keene is called into a meeting with the same Senator Thurman running the committee Charles told him about.

"Your sister's squadron wasn't hitting any of the targets they're talking about on TV," Thurman says. "They were on a mission to a facility in the mountains. Charlotte's plane went down, but a facility out of Turkmenistan picked her up. She's alive."

Good news! The problem? When Daniel goes to visit her in her special treatment center, she doesn't remember him.

So, what could that weird cloud be? And the goo?

There's obviously a reason why Charles' unit was sent on a mission to "a facility in the mountains," and you would imagine it has something to do with the bizarre cloud that seems to wreck their planes one by one. Could it be some kind of biological weapon, maybe a new defensive weapon, made by Iran? Perhaps something experimental that the facility they were attacking could have been working on?

It seems possible. But the other big question is, what happened to Charles' memory? Did the cloud, and the gooey substance in her cockpit, affect her neurologically?

Too early to say, but it seems a bit of a coincidence that Charles has lost her memory in the past, just as Juliette has lost her memory in the present. Surely there's a connection there...

Silo Season 3 is streaming now on Apple TV, with new episodes dropping every Friday.