I Know Who You Are

S3 E20: Barry and the team meet Tracy Brand (guest star Anne Dudek), a scientist, who may be the key to stopping Savitar. Unfortunately, Ki ller Frost is also after Tracy so Team Flash must battle their old friend, which proves to be particularly difficult for Cisco. Joe (Jesse L. Martin) and Cecile’s (guest star Danielle Nicolet) relationship takes a big turn.