"Criminal Minds," which premiered in 2005 and is still running as of 2015, has a sprawling cast headlined by Thomas Gibson, Matthew Gray Gubler, Shemar Moore and Kirsten Vangsness. In addition to these long-time stars, the show also boasts a sizable cast of secondary and supporting characters as well as many guest stars.
Other starring actors include A. J. Cook, Joe Mantegna and Paget Brewster. Brewster's run on the show ended in 2014 while Cook and Mantegna remained in its starring rotation through 2015. The long-running show has infrequently but reliably changed the composition of its core cast as it has aged.
Notable supporting cast members include Mandy Patinkin of "The Princess Bride" fame who appeared in 47 episodes between 2005 and 2007 as Jason Gideon and Jon Barton as a S.W.A.T. team leader. Jeanne Tripplehorn guest-starred as Alex Blake in a 48 episode run between the 2012 and 2014 seasons.
Guest stars of note in the show's history include Jennifer Love Hewitt, Timothy V. Murphy, Jane Lynch, Esai Morales, Tricia Helfer and James Van Der Beek. The show's procedural format means that guest stars come and go after appearing on the show for as little as a single episode or as much as an entire season-long plot arc.