Alex Parrish (Priyanka Chopra) seems closer to finding out who the real culprit in the New York terrorist attacks is in the next episode of "Quantico."

The trailer for the episode titled "Fast" showed that Alex could possibly get more clues regarding the identity of the terrorist. But she seems shocked to see where the clues are pointing at.

According to the synopsis for the episode, "In the future, Alex continues to search for the terrorist, and in the process, discovers some familiar faces – including one who knows the terrorist's endgame."

This could mean that someone close to Alex is behind all the terror attacks that FBI accused her of orchestrating. This could be one of her former classmates during the Quantico training.

Meanwhile, the trailer also showed Alex's best friend Shelby Wyatt (Johanna Braddy) doing her own thing to investigate about the terrorist. But she believes that both of them are going through a very dangerous suicide mission because of it.

In the previous episode, viewers found out that Shelby was the one driving the car occupied by Simon Asher (Tate Ellington) and Will Olsen (Jay Armstrong Johnson). But according to showrunner Josh Safran, viewers could soon find out why she was doing it.

"In the next episode, you will learn more about why Shelby was the one seen driving that car. It's a good one, the showrunner said in an interview with Entertainment Weekly. "And also, the end of the next episode, the very last moments pretty much — not pretty much — tell you directly what the rest of the season is going to be. From the very end of 19 on, we're pretty much in real time in the New York storyline and the master plan is revealed."

This could mean that Alex's days as a trainee in Quantico will soon be over.

"Quantico" episode 19 airs on Sunday, April 24, on ABC.