'The Rookie' Season 5 Promo Brings Back an Old Foe and Teases Secret Romance (Exclusive)

Nathan Fillion stars in the new season, which kicks off Sept. 25.

It's about to get real on The RookieOnly ET exclusively premieres the first season 5 promo for the ABC cop drama, and Nathan Fillion's John Nolan has earned the opportunity to choose his professional destiny.

The new season will focus on Nolan, who was the oldest rookie in the Los Angeles Police Department, as he's given the chance to decide where he wants his career to go within the LAPD. However, nothing is ever easy and the future is always complicated.

As the dramatic season 5 teaser previews, Nolan is unexpectedly reunited with dangerous serial killer Rosalind Dyer (Annie Wersching), whose psychological mind games puts him through his paces as he weighs his future. "People are going to die and you won't be able to save them," Rosalind eerily warns, as the promo cuts to various shots of the Rookie team.

Meanwhile, Chen (Melissa O'Neil) and Bradford's (Eric Winter) fake undercover relationship-turned-very real romance starts to show cracks as the pressure begins to mount. And their secret relationship isn't that much of a secret anymore as others start to pick up on their chemistry. 

The promo ends in a climactic moment when a sound of a gunshot puts everything on pause as Rosalind slyly looks away. "What have you done?" Nolan asks. Watch the intense promo above.

The new season of The Rookie will kickstart the franchise this fall, which will reintroduce Niecy Nash as she headlines the Rookie spinoff, The Rookie: Feds.

The Rookie premieres Sunday, Sept. 25 at 10 p.m. ET/PT on ABC.