"Criminal Minds" fans can expect to see several interesting guest stars appear in Season 11 of the CBS series in light of the departure of Jennifer Love Hewitt last season and the temporary absence of A.J. Cook.

Earlier this year, executive producer Erica Messer confirmed that Hewitt will not reprise her role as FBI undercover Agent Kate Callahan in the new season since she is taking time off to spend with her new baby. In addition, Cook is on maternity leave and will be missing in action during the first couple of episodes of Season 11.

To fill in for the lack of strong female characters, the show has cast veteran actress Aisha Tyler as the newest member of the Behavioral Analysis Unit (BAU) team. Tyler will play the reoccurring role of a forensic psychologist named Dr. Tara Lewis, who will bring an entirely new element to the police drama, teased Messer.

Fans can also expect to see a variety of guest stars, including "The Mentalist" star Tim Kang and Marisol Nichols of "Teen Wolf." Both Kang and Nichols will be featured in an episode airing on October 7 titled "The Witness." A synopsis of the episode reveals that Nichols will play a FBI agent who helps the BAU in preventing a vast attack on Los Angeles. Meanwhile, Kang will play a medical supply worker.

"When a Los Angeles bus is attacked with sarin gas, the BAU must act quickly to find the suspect before a larger-scale incident occurs, on CRIMINAL MINDS, Wednesday, Oct. 7 (9:00-10:00 PM, ET/PT) on the CBS Television Network. Guest stars include Marisol Nichols (NCIS, '24') as FBI Agent Natalie Colfax, who assists the BAU with the investigation, and Tim Kang ('The Mentalist') as Charlie Senerak, a medical supply worker," reads the synopsis, according to Carter Matt.

A photo of the upcoming episode shows Nichols in character as the FBI agent while talking to Dr. Tara Lewis and Derek Morgan.

Season 11 of "Criminal Minds" will premiere on Wednesday, Sept. 30 at 9 p.m. EDT on CBS.