A "Dawson's Creek" alum will make a special guest appearance as the BAU hunts down an Unsub involved in a triple homicide in Utah when CBS' "Criminal Minds" returns this Wednesday.

During the last episode, "Fate," David Rossi received the shock of his life when it was revealed that he had a 20-something-year-old love child. A TV reporter named Joy told Rossi that she is his daughter and that her mother is a woman whom Rossi had a passionate fling with almost three decades ago, reports Entertainment Weekly.

In the upcoming episode, "Amelia Porter," the BAU will investigate a triple homicide in Salt Lake City, which will lead the team to a fugitive from the past, reports the Hollywood Hills.

However, it was also revealed that the mysterious character Amelia Porter will be played by "Dawson's Creek" actress Avery Clyde, reports Unreality Prime Time.

CBS also issued a synopsis for the episode:

"When the BAU is called to Salt Lake City Utah to investigate a triple homicide, the search for a connection among the victims could lead them to a fugitive who could have ties to the UnSub."

Executive producer Erica Messer also opened up about an upcoming episode that will dig deeper into JJ's kidnapping, which took place last season during the epic 200th episode. 

According to Messer, the 11th episode will focus on JJ's character in wake of the tragedy, one year later. Because she has internalized the trauma, JJ will suffer from post-traumatic stress disorder that will resurface in different ways.

"It's coming out in unexpected ways. She's kind of internalizing it," Messer said, according to TV Guide.

Although her PTSD doesn't affect her job performance, it causes concern among her colleagues.

Season 10 Episode 10 of "Criminal Minds," "Amelia Porter," will air on Dec. 10 on CBS.

Read more about "Criminal Minds" here.