In "Rogue Time," an upcoming episode of "The Flash," Captain Cold (Wentworth Miller) and Heat Wave (Dominic Purcell) are back in town, but this time they're not alone. Peyton List joins the crew as Leonard Snart's younger sister, Lisa.

Check out the official CW description below.

"Rogue Time" - (8:00-9:00 p.m. ET) (TV-14, LV) (HDTV)

CAPTAIN COLD AND HEAT WAVE RETURN TO CENTRAL CITY; PEYTON LIST GUEST STARS AS LISA SNART - The Flash (Grant Gustin) learns that Captain Cold (guest star Wentworth Miller) and Heat Wave (guest star Dominic Purcell) have returned to Central City. This time Snart has brought along his baby sister Lisa (guest star Peyton List) to help wreak havoc on the city. John Behring directed the episode with story by Grainne Godfree and teleplay by Brooke Eikmeier & Kai Yu Wu (#116). Original airdate 3/24/2015.

"The Flash" airs Tuesdays on The CW at 8 p.m. EST.