The BAU will travel to Florida to track down a killer who alerts authorities before committing crimes. Meanwhile, David Rossi will connect with his long-lost daughter in the next episode of "Criminal Minds."

A preview video of the upcoming episode, "Anonymous," reveals the BAU will go on the hunt for an unsub who calls 911 to alert authorities about a murder victim right before he kills them. The criminal investigation will take place in Tallahassee.

This episode will also feature a plotline that centers on Rossi, his past and the return of his daughter, Joy, reports CarterMatt.

Joy was introduced last year in the episode "Fate" after Rossi discovered shocking news he had a 20-something, biracial love child. A TV reporter named Joy told Rossi she is his daughter and her mother is a woman whom Rossi had a passionate fling with almost three decades before, reports Entertainment Weekly.

While Rossi and Joy will have a chance to bond, he will also face more shocking news when he learns about the death of Harrison Scott, his former comrade in Vietnam. Scott was played by actor Meshach Taylor, who passed away in real life from lung cancer back in June 2014.

Before he died, his last acting performance was on "Criminal Minds" in Season 9, Episode 13. To pay tribute to him, actor Joe Mantegna requested the show commemorate his old friend in an episode in Season 10.

The synopsis for "Anonymous" states, "The BAU searches Tallahassee for a serial killer who calls the authorities to report the crimes prior to committing murder. Also, as Rossi prepares for a weekend visit with his daughter, Joy, he receives startling news about the death of a comrade in Vietnam."

Season 10, Episode 12 of "Criminal Minds," "Anonymous," will air on Jan. 21 on CBS.

Watch a preview below.