Last week's Fear the Walking Dead served up some pretty historic revelations about The Walking Dead universe at large and what other factions could be working to potentially rebuild society. The episode also featured a particularly tense climbing sequence, which saw Isabelle (Sydney Lemmon) and Al (Maggie Grace) attempting to scale a rock face to retrieve helicopter fuel stored at the top of an otherwise inaccessible cliff. CBR spoke with actor Maggie Grace about the practical nature of the filming, which saw her literally dangling from the edge of a cliff, reflecting the nature of the sequence itself.

"The End of Everything" catches up with Al following her kidnapping in the season premiere. We learn she has been taken by someone working for the same organization that scooped up Rick Grimes and Jadis back in Virginia. Isabelle winds up outlining the organization, and the information she gives, while broad, reveals this group to be the most advanced we've seen since the actual military fell alongside the rest of organized society. The two women are mistrustful of one another at first, but they cautiously find a way to work together that allows Isabelle to keep her group a secret and Al to stay alive.

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The climbing sequence becomes a key part of their truncated relationship, as they have to physically trust each other. Because she has designs on Isabelle's helicopter, Al has a motive to betray Isabelle, as she might be able to swipe the fuel and leave her behind. Isabelle, for her part, cautions Al strongly against this, because even if Al could overpower Isabelle, the organization wouldn't let her get far in a stolen chopper. Ultimately, Al and Isabelle reach a point of mutual trust that allows them to part on decent terms while giving audiences a better insight into what Isabelle's group is all about, their capabilities and their intentions.

But that cliff sequence.

"We had some guys - bless their hearts - we hooked in and then climbed up fairly high and the guys have the cameras on their backs. There’s some heavy pieces of equipment," Grace explained. "We shot there (on the rock face) - we did both. We did have some amazing stunt people as well. And then we had a wall built near the studio to match so we could get all the closeups, and get Isabelle hanging precariously off the side and do that safely." The moment she's referring to features Isabelle dangling by her harness off the side of the cliff while Al shimmies closer to a zombified climber whose equipment is more secure.

"And then the that third day we shot climbing stuff, we were up on the cliff and we had to be hooked in there for the scene where [Isabelle] tells Al what happened to her first partner." Al quickly deduces Isabelle killed that aforementioned partner. On top of the cliff, Isabelle reveals that she did it because he wanted to leave the organization, but operational security is so paramount that she was under orders to kill anyone who knew too much and tried to leave. So she did, and when she tells Al, Al realizes she is also a threat to Isabelle's operational security.

It's a heavy scene made more so by the conditions during filming to which the audience wasn't privy. "My only regret is you can’t tell how scary it was in this scene," she laughs. "The winds were so high we couldn’t even keep our eyes open there was so much debris in our eyes. And the clouds out front that came in were these weird, vertical storm clouds, there was a storm coming in. It was this really bizarre, surreal kind of moment. Really cool and it’s such an intimate scene, [but] there’s just all these very practical concerns… so it’s funny."

Airing Sundays at 9 p.m. ET/PT on AMC, Fear the Walking Dead stars Lennie James, Colman Domingo, Alexa Nisenson, Alycia Debnam-Carey, Garret Dillahunt, Jenna Elfman, Austin Amelio and Karen David.

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