WARNING: The following contains spoilers for Platinum End Episode 10, "Where the Tears Go," now streaming on Crunchyroll and Funimation.
The battle royale continues between the two main parties, Mirai's three-member group and Metropoliman/Hajime, and the stakes become more personal than ever for everyone involved, especially Nanato Mukaido. Hajime has taken Nanato's wife and daughter hostage, and Nanato and Mirai alone cannot rescue them and escape.
The villainous Metropoliman feels confident in his impending victory, and his peculiar ally Hajime Sokotani feels the same way. What no one expects is for Mirai's friend Saki Hanakago to gain new powers and properly join the battle for the first time. She also has her patron angel, Revel, to back her up in equally unexpected ways.
While Mirai and Nanato struggle to find a way to escape Hajime and Metropoliman, Saki Hanakago stays behind at the group's church base, worrying that her two friends have not yet returned. At the same time, Revel strains himself to absorb sufficient knowledge to become the new angel of wisdom, and thus become a first-rank angel and grant Saki new powers. Both characters feel powerless and frustrated, and when Revel sympathizes with Saki's feelings closely enough, he sheds tears -- a first among angels. Right away, the distant God takes note of this and congratulates Revel for breaking new ground among the angels.
Revel abandons his quest for knowledge and instead accepts the mantle of Revel, god of emotions, and his first-grade angel status means Saki now has her own wings. This is what Saki needed all along -- while she does have a fancy combat suit courtesy of Nanato Mukaido, she would be too vulnerable in battle without wings. Now she has them, and Saki prepares to make up for lost time and repay Mirai and Nanato for all they've done for her. She also clearly wants to repay Revel as well and make sure his hard work doesn't go to waste. Too many people are counting on Saki for her to just sit around -- she can and will put her newfound courage and resolve to good use.
Revel's hard work pays off immediately as Saki soars on her new wings to join Mirai, Nanato and their patron angels. The situation is dire, but Saki enjoys the element of surprise, and when Nasse encourages her, Saki fires her red arrow into Hajime's heart. Saki's gutsy move pays off, since Metropoliman never needed his own red arrow to control the ultra-loyal Hajime, meaning Hajime is now Saki's puppet. This gives Mirai and Nanato the chance they need to either flee the battlefield or capture Hajime and use him as leverage against Metropoliman.
Notably, Saki's red arrow has an incomplete effect on its target. Hajime's heart burns with adoration and respect for Metropoliman, his idol, and Hajime's heart becomes torn between Metropoliman and his arrow-induced love for Saki. The episode's final seconds suggest that Saki's arrow will overwhelm Hajime's adoration for Metropoliman, but if Metro himself returns to the battlefield and speaks encouraging words, Hajime's heart may become conflicted again and dilute or delay the effects of Saki's red arrow.
Either that, or Metro may simply kill Hajime to eliminate this liability. Already, Metro has used red arrows to kill friends and foes alike in cold blood, and he doesn't owe Hajime anything. Hajime's doom may be right around the corner, either at Nanato's hands or Metro's, and it all traces back to Saki's red arrow. One way or another, she makes a huge impact on this heavenly war in the new episode, and she can't take it back.
