Nana Mensah will be a series regular in The Diplomat Season 4. The actor has played Billie Appiah, the White House Chief of Staff, since Season 1.

Mensah joins Allison Janney (Grace Penn) and Bradley Whitford (Todd Penn), who have also been upped to series regulars in the fourth season, which is set to start filming this fall. The Diplomat Season 3 came out in full on October 16 on Netflix . Mensah’s promotion was announced by Deadline on November 4.

Mensah’s Billie started as Chief of Staff to President William Rayburn ( Michael McKean ). She was fiercely loyal to Rayburn and was one of the people trying to oust his vice president, Grace Penn (Janney), from her office earlier in the series. The plan was to replace Penn with U.K. Ambassador Kate Wyler ( Keri Russell ), b

See Full Page