There's a Frost warning in the latest poster for CW's The Flash.

RELATED: The Flash Creators Already Know Season 5’s Story

The new poster sees Danielle Panabaker's Caitlin Snow/Killer Frost front and center. The character famously took a villainous turn during the show's third season, with Killer Frost taking over Caitlin. Thankfully, in the season four premiere, “The Flash Reborn,” Caitlin was back and was (mostly) herself. However, it appears that the fourth season of The Flash isn't saying goodbye to Caitlin's evil persona anytime soon as the latest poster for the series, shown below, issues a chilling sign of things to come.

The Flash -- Image Number: FLA_S4_NovSwpW2.jpg -- Pictured: Danielle Panabaker as Killer Frost -- Photo: Nino Muñoz/The CW -- © 2017 The CW Network, LLC. All rights reserved.

The next episode of The Flash will surely bring about trouble for Caitlin Snow and Killer Frost as her former boss Amunet Black (Katee Sackhoff) is set to wreak havoc for Team Flash in "Girls Night Out."

RELATED: The Flash: Elongated Man Provides Another Clue in Thinker Mystery

Starring Grant Gustin as the Scarlet Speedster, The Flash airs Tuesdays at 8 p.m. ET/PT on The CW. The series also stars Jesse L. Martin, Tom Cavanagh, Carlos Valdes, Candice Patton, Danielle Panabaker, Keiynan Lonsdale and more.