Recall the long-haired version of 5-8 we saw in flashbacks escaping a mass grave. Now, we see the present-day one standing admiring piles of grilled refugees. Once again slain in mass by the Cheonmyeong Group, they are explicitly compared in the opening sequence of episode 5 of Black Knight.
See Also: Black Knight - Season 1, Episode 4 Recap
Things change and remain relatively unchanged at the same time. Progress is a mirage. Furthermore, Ryu Seok's only lead-the arrested man with the triangle tattoos-refuses to divulge the scope of his "relocation plan".
After winning the tournament, Sa-wol is also dealing with a personal crisis. The glimpse of his metal skull within the cut on his forehead triggers some of his memories from the day Seul-ah was killed, including taking a bullet to his own head. He now knows he’s a mutant.
Sa-wol gets a QR code, finally, and meets it with a, “Is that it”? Everything he has wanted his entire life now scarcely seems worth it.
He becomes the new 5-7. He gets his own place and his first assignment. But his mutant status, which is now public, puts him at risk, especially from Ryu Seok. However, it has also made him pretty famous.
Mr. Oh exclaims to Ryu Seok that Sa-wol is the healthiest mutant they've ever seen after inspecting him.
When Ryu Seok is last seen, he is receiving a blood transfusion. He appears to have a problem that he hopes to treat using a viable mutant's stem cells. This is based on dialogue excerpts, and one concludes that this is the purpose of the experimentation. He is obviously attempting to save himself at the expense of a great number of other people.
5-8 and the other former refugee Deliverymen decide to take matters into their own hands by kidnapping Ryu Seok.
Seol-ah meets with them. He reveals that the men with the triangle tattoos have had surgeries on their brains to make them emotionless. They simply perform their directives, kill targets, and then kill themselves.
5-8 hands over a lot of encrypted files to Seol-ah, but upon further investigation they don’t reveal any concrete connections to Ryu Seok and Cheonmyeong. She can’t go after him officially without that hard evidence, especially now that Ryu Seok, at the urging of his father, has amended the relocation plan to house refugees in the general districts.
But there is obviously a problem with this change. The migrants who have been rehoused must undergo medical exams and vaccinations. Because everything seems very suspicious, 5-8 orchestrates an attempt to free one of their prisoner agents. He thinks he's running away, but he really takes them right to Mr. Oh.
Since Mr. Oh is a coward at heart and is visibly afraid, it shouldn't be too difficult for him to provide information that leads to Ryu Seok.
It turns out that Ryu Seok is enacting another mass-murder plan.
Relocating the refugees to the general district allows him to get them all in one place - a place that he controls. In an effort to “purify” the air, he sends out trucks that deliberately pump dangerous chemicals into the atmosphere, keeping the environment inhospitable.
Cheonmyeong Group rose to power on the value of oxygen. As long as that precious resource remains at a premium, they retain their power.
With Ryu Seok’s off-site schedule in their possession, 5-8 and his team execute their next move, sabotaging the “purification” efforts. Seol-ah goes to meet with Ryu Seok’s father just as 5-8 holds Ryu Seok himself in the crosshairs of a sniper rifle, ready to take the shot.
Black Knight is now streaming on Netflix.
