If you're still coming to grips with Beth's death on the midseason finale of The Walking Dead, be warned: Things are only going to get worse.

"What you'll find in the back eight [episodes] is that people are reeling," Andrew Lincoln tells TVGuide.com of the fifth season's second half, which beginsSunday at 9/8c on AMC. "They reach probably their lowest ebb in Episode 10, which is an extraordinary moment in the show. It's probably the lowest point all of us will reach."

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But even though more heartbreak is coming, the show won't simply gloss over Beth's death. "All of them are suffering because of Beth," Lincoln says. "She signified a real innocence in the group... and [she] was so brutally ripped from their grasp. That that had a profound, seismic effect on the group."

In fact, the loss of Beth (Emily Kinney) inspires Rick (Lincoln) to lead the group to Noah's (Tyler James Williams) former community in hopes of finding sanctuary. "There was very much a paternal relationship between Rick and Beth... and there is something rather moving about the reason for the mission," Lincoln says. "Rick decides it's the only way that he can fulfill a dead person's wishes. I think that that's a beautiful thing. It's one of the most moving things Rick has done for a while, to honor her memory in that way."

Indeed, the first half of the season featured Rick at his most dangerous when he brutally murdered Gareth (Andrew J. West) and the rest of the Terminans. But Lincoln says that Rick hasn't completely gone over to the dark side. "He's like shifting sands — it is a constant reevaluation," Lincoln says. "I don't know if Rick necessarily believes that civilization exists, as we knew it. I think that he's reached a point where this season is him letting go of the old world. I think he's there — he's just waiting for the other people to catch up with him."

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However, Lincoln says it's the other members of the group that perhaps keep Rick from fully losing his humanity. "Rick is still morally anchored by his friendships," he says. "Daryl [Norman Reedus] still has a huge handle on him. With Michonne [Danai Gurira], you see a huge shift. Michonne and Rick's relationship is very interesting. There are still hugely formative and important friendships that have an influence on Rick and his leadership."

And yet, there are some members of the group — namely Father Gabriel (Seth Gilliam) and Eugene (Josh McDermitt) — on whom Rick is keeping a watchful eye. "You may not see it on camera, but certainly physically and spatially when we work together, there is a distrust — there was an arm's length between certain characters and Rick," Linocoln says. "Unless you've proved your worth, unless you truly have put your body on the line — you have to earn trust in this group. Once you've earned your trust, it's solid, and it's there for life."

But even if Rick has let go of the old world, he hasn't given up faith that a new world can be created, which is why he remains the group's best leader. "People ask: Does Rick have hope still? And of course he does," Lincoln says. "Otherwise, he would have cashed in his chips way, way earlier. He wouldn't keep pushing people forward. ... He believes that they have everything they need to start over. 'We're infinitely capable of surviving if we get four walls and a roof. Let's go. Let's fortify and let's begin again.'

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"This is a time in their lives where Rick instinctively knows, as good leaders generally do, that they need a marker," Lincoln continues. "They need somebody to drag them forward, because they're desperate now."

The Walking Dead airs Sundays at 9/8c on AMC. Watch the first two minutes of the premiere below.