FROST MUST FACE HER PAST – When a mysterious ice powered enemy frames Frost (Danielle Panabaker) for a brutal crime, she must find a way to clear her name. Meanwhile, Barry (Grant Gustin) and Iris (Candice Patton) have a surprise houseguest, and Joe (Jesse L. Martin) continues to deal with Kristen Kramer (guest star Carmen Moore). Original airdate April 13, 2021.