Lily Lambert, played by Anna Gunn in the backdoor pilot "Beyond Borders (2015)", was originally Jack Garrett's second-in-command. After the series was picked up by CBS, Gunn dropped out and was replaced by Alana De La Garza as Clara Seger.
Most episodes in the first season were aired out of order.
The Canadian owner of a subcontracted production firm that provided additional services for this show was murdered when he was vacationing in Belize while the first season was in post-production. In a morbid twist, the episode "Love Interrupted" of the first season takes place in Belize and has the IRT investigating the murders of three tourists, one of whom is Canadian.
Gary Sinise also starred in another crime drama spin-off on CBS, CSI: NY (2004) where he portrayed Detective Mac Taylor for 9 seasons. On that show, he led the New York City Crime Lab.
This is a second spinoff of Criminal Minds (2005). The first one, Criminal Minds: Suspect Behavior (2011) was canceled after one season.