Aisha Tyler has landed multiepisode arcs on two Emmy-nominated dramas: CBS’ “CSI: Crime Scene Investigation” and Fox’s “24.” On “CSI,” she will play a quirky scientist who comes to work with Las Vegas’ CSI team. On “24,” Tyler will play a data analyst who shakes things up at the Counter Terrorism Unit. She will debut in the third episodes of both series and will appear in three episodes of each show with an option for three more.