In an attempt to achieve his final form, Ultron had the company U-GIN build a bioorganic body in which he could upload his own consciousness. However, due to the Avengers coming to Seoul in order to thwart his plans, Ultron loaded the Cradle containing the body into a U-GIN truck, intending to complete the transfer once the Avengers were defeated. Using his sentries, Ultron attempted to reach a nearby airport.
Informed by Hawkeye, Captain America spotted the truck and jumped on it. Enraged by the assault, Ultron shot through the truck's doors to hit Captain America, who managed to grab the broken doors. Ultron and Captain America engaged in a brief duel on the truck's roof. Ultron forced Captain America to drop his shield on the road, but Black Widow, who chased the truck riding a motorbike, picked it up and caught up with the truck, giving Captain America his shield back.
The sentries still in the truck then shot at Black Widow, forcing her to take a side track. In the meantime, Ultron blasted Captain America off the truck. However, Captain America managed to return on the truck and resumed the fight against Ultron. As Ultron was attacked by a Quinjet piloted by Hawkeye, two sentries left the truck to take down the aircraft.
Keeping the fight, Captain America and Ultron left the truck, which was then found by Black Widow. As the truck headed towards a police roadblock, the two sentries who had left to fight Hawkeye returned and used their propulsors to take the truck's trailer in the air while the rest of the vehicle crashed into nearby cars.
Despite being trapped in the flying trailer, Black Widow managed to secure the Cradle. As Hawkeye positioned the Quinjet right behind the trailer, Black Widow cut the Cradle's ties so it could directly fall into the aircraft. Before jumping, Black Widow planted a bomb in the trailer which detonated seconds later, destroying the vehicle.