Joe Otterson TV ReporterRJ Cyler has been cast in a series regular role in the upcoming Issa Rae HBO Max comedy series “Rap Sh*t,” Variety has learned.The series follows two estranged high school friends from Miami, Shawna (Aida Osman) and Mia (KaMillion), who reunite to form a rap group. Cyler will play Lamont, an aspiring music producer with a sharp ear for talent.