(Warning: This post contains spoilers for the first season of The Get Down.) The Get Down begins with a flash-forward that sets up the narrative framing of the show: it shows protagonist Zeke telling viewers the end of his story before they even get to see the start. The adult version of Zeke (as played by Daveed Diggs) in the flash-forward is already an established rapper playing a massive show at what looks to be Madison Square Garden. When Zeke's younger self is introduced, played by Justice Smith, it becomes all about trying to connect the dots between that unsure but brilliantly talented teen and the self-possessed man he becomes. Daveed Diggs' cameo on The Get Down shows that Zeke will find success, even if we don't know yet at what cost it may come.
Aside from the importance to the plot, it is incredibly exciting to see Diggs in the role. Fresh off the monumental success of his dual role in Hamilton, Diggs is someone to watch. His Zeke functions primarily as a narrator catching viewers up on the events of the story as they unfold, but there's more to him than that. He's clearly a star, a man at the top of his game, and that's a big jump from the kid who dominates the story, the one who is just starting out and finds himself pulled in a million different directions.
Bridging the gap created by that initial disconnect between Adult Zeke and Teen Zeke is where Diggs' acting skills really come into play. It would be easy for him to perform the role as an impenetrable star who reveals very little and just exists to be an endpoint in the story, a contrast to Justice Smith. However, Diggs imbues his character with small moments of blink-and-you'll-miss-it vulnerability that make it a lot easier to see how that young boy grew up to be this man. Smith helps the transformation along on his end, too, as he shows Zeke begin to take step towards owning his strength and his abilities.
Diggs gives a lot to a role that really is a cameo at its heart. His character is glimpsed in very quick flashes, often imbedded in a montage, and a lesser actor wouldn't be able to stand out as much as he does. The small moments add to the depth of the character. They connect the flash-forwards to the world of the main story, despite the fact that they differ so entirely on the surface, from sound to style. It doesn't just show the evolution of Zeke's character but the evolution of the music itself, which is what The Get Down is all about.