Okoye and her fellow Dora Milaje, Nakia, accompanied T'Challa to the U.S. when a fund scandal needed to be dealt with. Shortly after they arrived to New York, the trio was threatened by Manuel Ramos—chief of a local group of criminals, whose front office was the south courtyard of the East New York housing project where T'Challa was staying. When Ramos pointed a gun at T'Challa and his bodyguards, T'Challa responded with a Wakandan gadget that electrocuted Ramos and the goons he had by his side. T'Challa then ordered his Dora Milaje to take care of the men, though he noted that killing them was unnecessary. Without their traditional weaponry, the Dora used their fighting skills to teach the bad guys a lesson. Later, Okoye and Nakia fought alongside T'Challa against Ramos himself in Hell's Kitchen.
When T'Challa later saved his former fiancée, Monica Lynne, from a scheme by the devious Reverend Achebe, Lynne recalled seeing the Dora Milaje in their early teens from her past time in Wakanda, and acted offended that he would spend time with them now that they are grown. Later, Okoye and the Dora Milaje followed T'Challa's orders to get Lynne to safety—but in the process, were chased by unknown criminals. Okoye, driving the group, stifled a yawn as she shot at the assailants, driving their vehicle into the East River. They emerged in a flying amphibious craft with 150 heavily-armed Wakandan Special Forces Group soldiers on board. The group then returned to Wakanda just as a war broke out at the hands of Achebe.
On the way home, Nakia called Lynne a spoiled American witch in Hausa. Okoye reminded her to not say such things as Lynne has always been the King's beloved. And while Nakia agreed, she said she always despised her. Okoye offered advice to her sister in arms about their station and duty, but Nakia refused to listen, believing that the King loved her and only her. The crew arrived in Wakanda to find it being destroyed by Prowlers, giant robot panthers and doomsday weapons. T'Challa ejected from the craft to deal with the matter as Lynne, finally fed up with the bickering, engaged with Nakia in the cockpit. Lynne called her out for being delusional about her relationship with the King, calling her a child. Nakia then forcibly ejected Lynne from the craft, and later claimed to T'Challa that she was dead. T'Challa refused to believe her and refused her services as Dora Milaje, banishing her from Wakanda.
Nakia was later captured by Achebe and tortured until Killmonger freed her. He used the Altar of Resurrection on her which bestowed enhanced abilities upon her, turning her into Malice, an enemy to Okoye and T'Challa. Meanwhile, Okoye accompanied T'Challa to recruit the Chicago-raised Queen Divine Justice for the Dora Milaje, and ended up working well alongside her.
Later, after a brain aneurysm caused T'Challa to go into hiding, Okoye went with him. They encountered a man named Kasper Cole who was improperly using the garb of the Black Panther as an urban vigilante. T'Challa chose to test Kasper to see if he was worthy of the role. The trial of character aimed to see if Kasper would abandon his pregnant girlfriend due to his attraction to Okoye. Though he was challenged by the test, Cole ultimately won the approval of the Panther, and later fought alongside him.