AJ Cook. K likes. This is the official page of AJ Cook Actress, Producer, Mother, Fitness Enthusiast, Nature Lover, Beach Bum Hippie. Best Known: Andrea Joy "A. J." Cook is a Canadian actress known for her role as Supervisory Special Agent Jennifer "JJ" Jareau in the CBS crime drama Criminal Minds. A.J. Cook in Still married to her Husband Nathan Anderson? Who is Andrea Joy Cook dating in ? Relationship status: Married (Since ) Sexuality.