WARNING: If you don't want to know what happened in this episode, don't read this photo recap!
Remember that time that a full-grown man about to die by Lyta's hand told her he was her son? Right. So Adam comes in, and recognizes him as General Zod — Superman's greatest enemy. He's also from the future, which makes the mother-son relationship less creepy.
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With a gun pressed up against his chest, General Zod starts talking. He knows some Kryptonian history: Brainaiac isn't from the future – he's from the present, come to destabilize Krypton by staging a coup in Kandor. This sets the works in motion for Krypton to eventually explode, a fact Seg isn't pleased Adam hid from him.
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Seg and Lyta tie both Adam and General Zod up, and ask for some answers. Zod is in quest of a weapon so powerful that even Brainiac is defenseless before it. It's somewhere close to the Superman sigil and Seg knows where that is. The cavedwellers in this place are guarding it, though.
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Meanwhile, Jayna is busy swelling the ranks of the insurgency. She gets Dev-Em on board.
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During an absolution ceremony, Daron-Vex pardons a rankless Black Zero member who just received his unction. This is against protocol. But this person will eventually be framed for the murder of Rao, and they needed to separate him out. Sneaky sneaky.
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Seg is not convinced by Adam's defense, and so leaves him tied up as he, Lyta, and General Zod go searching for the big powerful weapon.
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The Voice of Rao, hijacked by Brainiac's sentry, offers "eternal life" to little Ona. That would entail him uploading her into his head, just like all the other intelligent lifeforms he's acquired. She needs to sleep on it.
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Remember that little stunt back at the ceremony? Well, Daron isn't pleased with how Jayna handled it. Pardoning the rankless was too public, too drama. And considering that they're going to be blowing Rao up at a special ceremony, the last thing they need is premature fireworks.
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When an officer expresses his concerns of foul play regarding the pardoned prisoner, Jayna at first praises him. Then she kills him.
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While navigating the tunnels, the trio are ambushed by the underground dwellers (tipped off by Adam). They vanquish their assailants easily.
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Ona eventually chooses not to get sucked up into Rao's mind. She likes being able to walk around and stuff, and also three dimensions.
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Dev-Em, who's planted the bomb that's going to blow Rao sky-high, enters the godhead's chambers, and informs him it's officially showtime. But Rao has a slight change of plans: he wants there to be lots of people at the ceremony. People + explosion = mass casualties. Let's see how Dev-Em gets out of this one.
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Seg, Lyta, and General Zod find the Superman sigil, and use their blood to open a door protecting the weapon.
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That weapon is this. Doomsday.
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Adam, and behind him the underground dwellers, rush to the scene to stop Doomsday from getting out. If it does, they claim, it will surely kill everything in the universe.
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A firefight breaks out. General Zod wants that weapon!
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The gang make it out alive, though General Zod's been hit. Seg tells Adam to take a hike once they're back in Kandor: he's teaming up with the Zods.
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Dev-Em leads the Voice of Rao to the place where he will be assassinated. That's where he demasks, and shows off his beautiful black eyes and long, strong tentacles. He sucks up all their brains.