Warning: This article contains spoilers about Sunday’s episode of The Walking Dead, “Open Your Eyes.”

If you’re looking for a doctor in Alexandria, you may want to look elsewhere.

Sunday night’s episode of The Walking Dead focused largely on Siddiq (Avi Nash) and his mental health after having been forced to witness the brutal murders of 10 of his friends and neighbors — including Enid (Katelyn Nacon), Tara (Alanna Masterson), and Henry (Matt Lintz) — at the hands of Alpha (Samantha Morton) and the Whisperers last season. And the good doc was struggling.

The season already had introduced the idea of Siddiq battling with PTSD and bonding with his fellow white-coat, new guy Dante (Juan Javier Cardenas), over it. Now he’s restless and having difficulty sleeping between his nightmares and sleepwalking to the top of the windmill, and that issue is compounded by the fact that an inordinate amount of Alexandrians — including his baby mama, Rosita (Christian Serratos) — is sick.

Insomnia appears to be making him a bit delusional and even suicidal after he seemingly put hemlock in his medical bag when he went to treat Carol and Daryl’s Whisperer captive, whom Dante then killed when he “accidentally” gave it to the prisoner. It’s only after Siddiq jumped in the lake and was saved by Rosita that he realized something was amiss with the community’s drinking water.

As we already know, part of Alpha’s plan is to poison Alexandria’s water supply. What we didn’t realize was just how insidious that plan was — and that it involved a Whisperer plant in Alexandria to see it through.

In the final moments of the episode, Dante visits his so-called “friend” Siddiq to apologize for what he claims to be a water mix-up. But when Siddiq hears Dante make a certain clicking sound with his tongue, he realizes it’s something he’s heard before… amid that devastating Whisperer attack. He has an epiphany — Dante fed the Whisperer captive the hemlock! Dante fed the Alexandrians tainted water! Dante is the man who told him to “open his eyes” during the attack! DANTE IS A WHISPERER! — and it shows on his face before he has a chance to reach for a weapon.

“I didn’t want this. Not you, not like this,” Dante says as he strangles Coco’s dad to death. “Close your eyes,” he whispers.

While Siddiq only entered the picture at the beginning of season 8, he is the living embodiment of the legacy of Carl Grimes (Chandler Riggs), who was bitten by a walker and died trying to save the doctor and bring him into the Alexandrian community. Carl’s vision for the future of Alexandria, which has mostly come true, Negan (Jeffrey Dean Morgan) picking tomatoes and all, absolutely included Siddiq. But with the death disappearance of his father Rick (Andrew Lincoln), the impending departure of Michonne (Danai Gurira), and now this, is the end of Alexandria as we know it — and as Carl dreamed it — upon us?

“I think Siddiq very much fought to uphold his promise to Carl,” Nash said on Talking Dead following the episode. “In season 9, we saw how committed he was to upholding his promise to Carl… and he really fought to get the communities together.

“If anything, this season, there’s been a little wrench thrown in the works with all the PTSD,” Nash added. “He’s really a bit town between whether he wants to continue this message of mercy or if he wants to lean into the wrath a little bit. I think revenge was on his mind because he’s in a waking nightmare all the time.”

Sitting beside Riggs, Nash also spoke about their big scene together several seasons ago.

“It’s funny, Chandler very much was the first person to bring me into the family… and in your final episode you said something like, ‘Welcome,’ and, ‘You’re stuck with us now,’” he said. “I remember that being, besides really good acting, really truthful. I was like, ‘Whoa, I am here now and the torch is sort of passed.’ I hope that, now that I’m leaving, I can pass that on to the next set of actors that will sit on this couch and one day also die.”

Following the episode, many fans were understandably emotional.

Many fans also joked about the fact that the show has rarely been able to keep more than one doctor alive at a time.

The Walking Dead airs Sundays at 9 p.m. ET on AMC, followed by Talking Dead.

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