Attack on Titan Episode 20: Erwin Smith: 57th Expedition Beyond the Walls (4)

Jean and Armin shift positions in the trees as a Titan climbs higher toward them, with Jean noting how frighteningly quick the Titans are to adapt.

Eren wonders aloud if the captured Female Titan is an abnormal like the Colossal Titan, but Oruo and Petra urge him to focus on advancing deeper into the forest and standing by.

Levi perches on the Female Titan's head, sarcastically demanding the person inside emerge and threatening to sever its limbs, while Erwin orders more wires fired and explosives readied at its wrists after it hardens its hands over the nape.

The Female Titan emits a piercing screech audible even at the forest's edge, drawing other Titans that swarm and begin devouring it despite the Scouts' efforts to protect the body.

Erwin, sensing defeat and that the enemy values its secrets enough to risk being eaten, signals a blue retreat flare and instructs Levi to restock gas and blades before withdrawing.

In the trees, Christa and others worry as Titans climb trunks but can't reach high enough, puzzled by distant cannon blasts; Reiner questions how cannons were brought inside, while Eld affirms Erwin as humanity's hope, trusted fully by Levi.

Petra thanks Eren for his earlier trust in following orders, though Oruo calls him a brat who should know his place; Eren notes Erwin's lack of transparency suggests distrust in rookies.

As squads prepare to retreat excitedly to see the captive's face, a mysterious green flare fires from elsewhere, drawing Gunther and his team to investigate despite the danger.

The group pursues into peril, where an enemy using ODM gear ambushes and kills Gunther and his squad in human form, confirming Erwin's suspicion of a traitor among them.