The Beginning of the War! Ace and Whitebeard's Past!

Three more vessels slip into the bay alongside the Moby Dick, and Whitebeard, watching from the deck, hopes aloud that his son is unharmed. Below at the Gates of Justice, Ivankov asks Luffy whether Dragon will appear to rescue Ace, since no father would let his child die. Luffy corrects him: although Dragon is Luffy's own father, Ace was born to Gol D. Roger. From there the episode dives into Ace's memories, replaying the path that carried him to the rank of Second Division commander.

The recollection moves through his parting with Luffy, his early days commanding the Spade Pirates, and a chance meeting with Shanks on a snowbound island, before reaching his confrontations with Jinbe and Whitebeard.

Ace turns down a Warlord seat and seeks out Whitebeard, fighting Jinbe along the way. After repeated failed attempts on Whitebeard's life, Ace gradually accepts the old captain as his leader and adoptive father, bonding with the rest of the crew and climbing to division commander. The flashback ends with Ace leaving against orders to chase Blackbeard, who had betrayed the crew and killed Thatch. In the present, Ace asks why they would come for him after he defied them, and Whitebeard answers that Ace is his son and the fault for the Blackbeard pursuit was his own. The episode also marks Whitebeard demonstrating his Gura Gura no Mi before the Marines.

An animation slip shows Shanks with both arms during the meeting with Ace, corrected in the home release. The anime adds Thatch and Ace fighting the Decalvan Brothers, and depicts Teach stabbing Thatch in the back, details absent from the manga. This is also the first time Whitebeard laughs with his signature Gurarara in the anime. The episode introduces new voice actors for Ivankov and Mihawk, and debuts numerous Whitebeard commanders along with the Gura Gura no Mi.