Lois is putting her mother's gift, the bluebird of hope, in the window of her new apartment when Clark comes in with more boxes to be unpacked, including one with her Whitesnake throw pillow. She tells him that she's talked to Oliver and Chloe and they're doing fine in Star City. Clark wants to unpack at superspeed, but Lois tells him that they need to take the time to find the perfect spot for everything. Tess calls to inform them that Slade Wilson was found in a coma, lying on a street corner. Clark realizes that a member of the El family must have released him from the Phantom Zone where Clark sent him.
At Watchtower, Clark has Tess prepare the device to send him to the Phantom Zone. Oliver arrives and says that he's going with him, and Clark realizes that Tess told his friend. She says that Clark will be powerless, and Oliver has more experience with that condition. Clark refuses, saying he has to do it alone, and Tess provides him with a communication device that will bridge the two dimensions. Tess activates the Phantom Zone projector and tells Clark to be careful, and Clark starts to enter the portal... and Oliver jumps in after him.
Clark and Oliver arrive in the Zone and Clark complains that Oliver came with him. They start exploring and find mounted skulls with the Omega brand on them. Clark contacts Tess and then realizes that the prisoners are nearby. They get to the portal device and discover that the crystal that opens the gate is gone, meaning they have no way back. The phantoms fly in and attack.
On Earth, Lois arrives as Tess hastily turns off the communication device so she can't hear what Clark is suffering from. The crystal signal cuts out and Tess is unable to reestablish contact, meaning the communicator has been destroyed. Lois wonders what to do next, and Tess admits that they don't have an alternate plan.
The phantoms bring Clark and Oliver to a throne where a hooded figure is seated on a throne. He reveals that he is Zod, and calls upon them to kneel. The Zoners take Oliver away and Zod beats Clark down. Clark vows to defeat him without his powers, and Zod explains that when he arrived, he met the original Zod's phantom. The phantom has entered his clone body, giving him the knowledge of two lives. Zod draws a sword and hits Clark when he dares to defy him, then asks what Jor-El would think of Clark having sent Slade there without a trial. Clark realizes that Zod sent Slade back to lure Clark there. He sees the control crystal on a cord around Zod's neck, and Zod explains that he has some of Clark's blood from when Clark healed him on Earth. Clark insists that he saved him because it was the right thing to do, but they have no other connection. Zod insists that as Kryptonians, they were meant to be leaders, and that he only puts his faith in himself. He reminds Clark of the story of Cain and Abel, and Clark says that he would never murder Zod. Zod hits him again and tells Clark that he'll learn what it means when Zod is in charge.
The Zoners escort Clark to a crude arena where two of them are fighting. Oliver is in a cage and explains to Clark that Zod plans to have Clark fight to the death. One of the gladiators wins and then attacks Clark, who defends himself with a shield until it's broken. Oliver tosses him a discarded helmet which Clark uses as a club to knock the gladiator out. The crowd calls on Clark to kill him, but Clark refuses and throws away his makeshift weapon. Zod tells the crowd that in the arena, they answer failure with death. He draws his sword and approaches Clark, and then kills the fallen warrior. Zod says that it's kill or be killed in his world, and warns Clark that the next time he fails to kill, he'll suffer for it.
As Tess checks her computer repeatedly, Lois grows increasingly worried and tells her that she has to work harder, and then tells her to check the crystal laser. Tess reluctantly agrees to do so, and Lois checks the computer, which reveals that Tess is planning to destroy the gate in just over two hours.
Clark is locked up with Oliver, and explains that he and Tess put a plan in motion to destroy the gate by setting it to self-destruct. He admits that Lois doesn't know, and plans to get them out of the Zone before it's too late. Clark explains that he's read everything Jor-El wrote about the Zone, and he knows how Zod thinks, but Oliver isn't convinced.
Tess confirms that the crystal is fine, and returns to discover that Lois has figured out her plan. She explains that Clark knew the risks, but Lois accuses her of turning on her friends. Tess insists that she's following Clark's orders, but Lois doesn't believe her. She draws a gun, but Tess insists that they have a responsibility and they can't risk the world for selfish reasons. Lois refuses to let Tess sacrifice Clark, but Tess says that Lois will have to accept that being married to a hero means accepting a hero's sacrifices. In response, Lois says that it means refusing to accept defeat.
Zod has Oliver brought to him and taunts him into growing angry. He then explains that Darkseid came looking for him in the Zone and promises him lordship over the Zone if he disposed of Clark. Oliver insists that they've defeated Darkseid and his three minions, but Zod warns that there are millions under Darkseid's influence, including Oliver. He points out that Oliver has always been filled with anger and a desire for revenge, and is now at Darkseid's beck and call. Zod asks what Clark would think if he knew, and Oliver insists that Clark would still stand by him. Zod doesn't believe it, and warns that Clark would eventually cast Oliver aside, just as he did with Zod. He offers Oliver the chance to rule at his side as a brother, now that he has realized he has nothing in common with Clark. Zod removes Oliver's manacles and promises that since Clark will never embrace his dark side, he will die in the Zone. He tells Oliver to draw on the darkness or die.
Later, Clark is given a sword and shield and led into the arena, and discovers that he will be fighting Oliver. Oliver brutally attacks Clark, who finally fights back. He lunges at Oliver, who impales him with a sword. Oliver prepares to deal the final blow and Zod tells him to stop. The Zone's ruler steps forward and draws his sword, and then welcomes Oliver as his brother in arms. However, he says that he'll be the one to deliver the death blow. As he raises his sword, Oliver grabs his arm and Clark grabs the control crystal. He uses it to open a portal, and the sunlight from Earth heals his wound. Clark then tells Zod he'll have no more second chances, enters the portal with Oliver, and destroys the crystal once and for all.
Later, Tess tends to Oliver's wounds, while Clark explains that that was their plan all along, and he knew he could trust Oliver to play his part. Once Tess leaves to call Emil, Oliver warns that the Darkness appears to be everywhere and wonders what will happen if it comes back. Clark says that they will fight it, and Oliver asks what they would do if one of them was infected by the Darkness. Clark says that they'd have to lock the victim up because he doesn't believe that there's a cure. When Oliver says that Zod said several things to him, Clark warns that Zod knows how to play on other's fears and mostly lies. Oliver tells him to go see Lois and Clark superspeeds away.
Clark returns to the apartment and Lois runs to embrace him. He realizes that she's unpacked everything without waiting for him, and wonders how she did it so quickly. Lois explains that he and Oliver have been gone for three weeks, while Clark only experienced a few hours. She describes how she waited for him, and Clark asks why Tess didn't blow up the gate. Lois tells him that she brought Tess around to seeing things her way, and wishes that Clark would have had faith in her. When Clark says that he was trying to protect her, Lois insists that he's part of her and that in the future, he warn her of the risks. Clark admits that sometimes his more controlling Kryptonian side takes over. Lois tells him that they are two days from their wedding, and she couldn't bring herself to postpone it. Clark assures her that there's nothing that could prevent him from walking down the aisle with her.
Oliver meets Tess, who has information from the Veritas journals on a constellation known as the Bow of Orion and its coordinates on Earth. He explains that Carter Hall was looking for the Bow, which was used by the last warrior to defeat Darkseid. Tess says that it's not his quest, but Oliver says that he has to do it and Tess agrees not to ask any questions. Oliver then goes to a church and goes through Carter's journal while remembering the violence he's committed. After a moment's hesitation, he walks by a statue of an angel, which weeps blood as he goes.