The CW has released an official description for the third episode of The Flash.

It’s called “Things You Can’t Outrun” and here is how they describe it. Robbie Amell guest stars!

THE FLASH BATTLES THE MIST, CAITLIN TELLS BARRY ABOUT RONNIE —As Barry (Grant Gustin) and the team at S.T.A.R. Labs work to capture Kyle Nimbus (guest star Anthony Carrigan), a.k.a. The Mist, a dangerous new meta-human with toxic gas powers, they revisit the painful night the particle accelerator exploded and killed Caitlin’s (Danielle Panabaker) fiancé, Ronnie (guest star Robbie Amell). Meanwhile, Joe (Jesse Martin) decides to finally visit Henry (John Wesley Shipp) in jail after all these years, but things take a dangerous turn when Kyle shows up looking to punish Joe for arresting him years ago. Meanwhile, Iris (Candice Patton) and Eddie (Rick Cosnett) continue to hide their relationship from Joe. Jesse Warn directed the episode written by Alison Schapker & Grainne Godfree (FlashTVNews #103). Original airdate 10/21/2014.

“Things You Can’t Outrun” will air on October 21. Read some more Flash spoilers on our Flash spoilers page!