McCormack plays Dr. Daniel Pierce, a schizophrenic neuropsychiatrist who assists the FBI on complicated cases.
Qualls is best known for his work in the films "Road Trip," "The New Guy" and "Hustle & Flow." He is now part of the cast of TV's "Legit" and plays a recurring role on "Supernatural."
"In 'Perception,' Qualls will play Agent Rudy Fleckner, a young, tech-savvy FBI agent who specializes in investigating cybercrimes," TNT said in a synopsis.
"When an online social game Caleidoscope becomes the center of a homicide case, Pierce relies on Fleckner to decipher the clues within this virtual world. By digging into a suspect's online account Fleckner hopes to bring forth evidence that sheds light on a case in which the line between reality and fantasy becomes blurred."