The Walking Dead S4B Key ArtCarl Grimes’ star in The Walking Dead universe continues to rise. After his father Rick had dominated The Walking Dead posters since the hit series’ launch, he is now sharing the spotlight with his son. The poster for the second half of The Walking Dead Season 4 released today  features Carl Grimes (Chandler Riggs) and Rick Grimes (Andrew Lincoln) with the tagline, “Don’t Look Back.”