As for who Nyong’o might play, Marvel isn’t saying, but Black Panther has had several crucial relationships over the 50 years since his introduction — the most significant being Ororo Munroe, otherwise known as The X-Men’s Storm. The pair were married in a 2006 storyline that tied in to Marvel’s Civil War crossover event (the basis for, yep, Captain America: Civil War), but later divorced. Rule that one out however — Fox holds film rights to all X-Men characters, and Storm is currently played by Alexandra Shipp in X-Men: Apocalypse.
Marvel’s Kevin Feige is producing the movie, which continues a storyline first introduced in Captain America: Civil War about a prince of an African nation who rises to fight after his father’s murder at the UN. Black Panther is scheduled right now to debut in theaters on February 16, 2018.