The story of Falcon's journey into becoming the new Captain America will play out in upcoming Disney+ series The Falcon and the Winter Solider which also stars Sebastian Stan as Winter Solider.
"We started shooting a few months ago. We're almost done and the shield is in good hands," Mackie told Colbert on Tuesday.
Mackie also talked about the significance of having a black man portray Captain America.
"For Marvel to select a young black man in America to represent the moniker of Captain America is unprecedented. There's nothing that can compare to that," the actor said.
Mackie mentioned that he is moved by the thought of his kids and children of all races seeing a black man as Captain America.
Colbert also presented to Mackie comic book artwork of himself as Falcon flying through the air.