Psychopathic serial killer Zito, an evil genius whom Mac helped arrest and convict, is up for parole due to gullible psychologist Marion Skinner. Mac testimony, a sharp analysis, prevents his release, but the court appearance allowed Zito to steal a pen and escape, fatally stabbing two staff members. He also leaves a complex series of arithmetic riddle clues. Each points to a place or victim, part of an elaborate trap to teach MacGyver a master class in evil, but unlike the police, Mac proves at least as smart.
—KGF Vissers