Amuro is practicing on docking the Core Fighter with the Gundam modules released by the Gunperry piloted by Ryu. A distress signal coming from a nearby location is detected by Fraw. Bright orders Amuro to fly over to the location with the Core Fighter. Amuro ejects the Core Fighter from a crouching Gundam and takes off. Ryu is disturbed at the position the Gundam is left in.
Amuro approaches the island the distress signal is coming from. He detects a downed Federation fighter aircraft and lands the Core Fighter nearby.as he approaches the plane he spots two wounded pilots and tied with ropes to their seats. He reports back to Bright and he then tells Mirai to prepare battle stations in case of ambush or trap.
Amuro unties the pilots and lays them both on the beach to check their wounds. One of them dies, and when Amuro goes to look at the other pilot he gets pelted with rocks. Amuro grabs the pilot and takes him to the plane for shelter. The pilot dies too, however. A distressed Amuro shoots at where the rocks are coming from and runs up to a hill.
Flares are thrown at him, and he sees that three children are the ones throwing the things. They yell at him to leave the island, so he runs back to his Core Fighter. A Zaku II piloted by Cucuruz Doan appears, and through the loudspeaker asks Amuro to surrender. Amuro says he cannot do that. Doan says he doesn’t want to fight. Amuro takes off and fires its missiles at the Zaku. Doan dodges one missile and picks a boulder and throws it at the second missile. The ensuing blast blinds Amuro and forces him to crash into the ocean.
When Amuro wakes up in a cabin he meets a young woman named Rona. He collapses to the floor; Rona tells him he shouldn’t be moving so soon. Amuro finds Doan working on a field and asks where is his Core Fighter. Doan refuses to say where it is. He knows Zeon will come for him soon, and that he has to protect the children. Amuro contends that he needs the Core Fighter to defend himself from the enemy. Doan says that Amuro will attack him if he hands over the fighter. The children tell Amuro again to leave. Amuro desists and searches the plane on his own.
Amuro stands on the top of a waterfall and surveys the island. He deduces that Doan could have moved the fighter very far from where it was. He takes a bath and as he sits on the beach he is joined by Rona. She tells him he doesn’t know how beautiful the sunset is. Amuro replies saying that in war, nothing is beautiful. Amuro asks why Doan is using the children making them stay with him. Rona tells him he doesn’t know what he’s talking about.
Ryu is searching for Amuro when Bright orders him to return to the ship for the night. Fraw is worried about Amuro. On the island, Doan is having a nightmare flashback. He is piloting his Zaku in battle and sees the children crying over the lifeless bodies of their parents. He wakes up and searches the radar for any signs of Zeon. He tells Rona that they have to leave the island given that they can’t change Amuro’s opinion.
The next day, White Base continues its search for Amuro. Fraw detects several objects moving toward the area Amuro went to. Bright orders Mirai to change course to that direction. Amuro is still searching for the Core Fighter when the kids start throwing rocks at him again, telling him to leave. He hears something and sees a Luggun with a Zaku holding onto it. The Luggun shoots at the children, and Amuro saves the girl from falling.
They return to the cabin and Amuro asks Doan for the Core Fighter. The Zaku lands and destroys the cabin. Doan takes Amuro to a cave behind the waterfall where the Core Fighter and Doan’s Zaku are concealed. Ryu approaches the island and Amuro launches from the waterfall. Doan attacks the Zaku but falls when attacked by the Luggun. amuro asks Bright to perform a midair conversion. Amuro converts to the Gundam and returns to fight. He destroys the Luggun but Doan tells him to leave the Zaku to him. He says he will fight on as long as the children live. He explains that when he accidentally killed the children’s parents, he was ordered to kill them too. He instead fled with the kids. Doan destroys the Zaku and throws it into the ocean.
The fight is over, and Doan says they’re no longer safe. Amuro throws Doan’s Zaku into the ocean to the children’s protest. Doan tells the children that Amuro did the right thing.
When Mobile Suit Gundam was released in North America, director Yoshiyuki Tomino felt that the episode was not on par with the other episodes and requested that it be cut from the North American lineup. Subsequently, the episode Sayla's Agony is listed as Episode 15 in the NA release.