CBS drama NCIS: New Orleans is expanding its regular cast with the promotion of recurring players Shalita Grant and Daryl Mitchell. They join returning stars Scott Bakula, Lucas Black, Zoe McLellan, Rob Kervovich and CCH Pounder.

Grant, who appeared in four episodes from Season 1, plays Sonja Percy, a whip-smart ex-ATF agent who is used to — and most comfortable with — operating undercover and alone, and will now have to adapt to work as the newest NCIS Agent alongside Pride (Bakula) and his team. Wheelchair-bound Mitchell, who guest starred in 11 episodes, plays Patton Plame, a confident and brilliant Investigative Computer Specialist for NCIS, who has a long-standing competitive history with Agent Pride and a budding competitive rivalry with Forensic Scientist Sebastian Lund (Kerkovich). Grant, who is currently shooting the BBC miniseries Mercy Street, is repped by D2 Management and TalentWorks. Mitchell’s previous series credits include NBC’s Ed and Fox’s Brothers. NCIS: New Orleans will launch its second season on September 22 in its post-NCIS Tuesday slot.