"The Flash" Season 3 is ready for an all-new episode in which Barry Allen come across three villains from the past Eddie Thawne (Rick Cosnett), Ronnie Raymond (Robbie Amell), and Leonard Snart (Wentworth Miller). This confirms that the trio belongs to the Speed Force as Barry heads out to save Wally after being influenced. 

Previously, "The Flash" Season 3 Episode 15 featured the comeback of Savitar. The rogue played with Wally's head and Iris' brother allowed Savitar to escape from the prison, thus, letting Wally take the villain's place. However, the released promo for Episode 16, titled as ' Into the Speed Force,' will confirm that the three villains are a part of the Speed Force, reports Comic Book

Barry is trapped in a predicament as Wally is being manipulated by Savitar. He accidentally set Savitar free from the prison and handed him the rest of the philosopher's Stone. He was also forced to take Savitar's place in the Speed Force before Barry could stop him. Eventually, Wally is stuck in the Speed Force and Savitar's prediction is taking a new turn. 

Previously, fans witness the romantic union of Wally and Iris. However, at the end of the episode, Iris was seen without an engagement ring and their romance was short-lived as she realized that Barry asked her out to keep her protected. 

According to the final synopsis of "The Flash" Season 3 Episode 16, Barry is apprehensive to get some answers as he tries to stop Savitar and save his friends. Moreover, H. R gives Jesse some advice. 

The executive producer Andrew Kreisberg of "The Flash" told EW "Barry's so desperate to save Iris that he is starting to lose it a little bit. It's not that Barry doesn't want perfect marriage with Iris, it's not that she doubts her love for him, it's just that's not exactly every girl's dream."

"The Flash" airs Tuesday on the CW. It is written by Brooke Roberts and Judalina Neira.