He played Richard Slessman, an assistant to the unsub, Vogel, that the BAU team was trying to find.

Source: https://collider.com/celebrities-that-played-unsubs-on-criminal-minds/

Once he realized they were stronger together, he became an integral part of turning the BAU into a family.

Source: https://www.cbr.com/great-characters-flaws-drama-tv/

One of the commentators, introducing himself as an employee of the BAU restaurant, said that the employees had gone home, there was no security, and only management remained in the restaurant.

Source: https://akipress.com/news:742249

On the heels of Prentiss' departure from the BAU, Jeanne Tripplehorn's Alex Blake was introduced in season 8. Soon, Alex eventually became an important member of the BAU, working closely with the rest of the team and developing a bond with them.

Source: https://screenrant.com/criminal-minds-evolution-season-2-character-return-possible-derek-morgan/

On the heels of Prentiss' departure from the BAU, Jeanne Tripplehorn's Alex Blake was introduced in season 8. Soon, Alex eventually became an important member of the BAU, working closely with the rest of the team and developing a bond with them.

Source: https://screenrant.com/criminal-minds-evolution-season-2-character-return-possible-derek-morgan/