Fresh from Comic-Con 2018, this SUPERGIRL trailer gives fans a look back at some exciting highlights from season three, plus a taste of what is come in the show’s fourth season, including a sneak peek of new series regular Sam Witwer as iconic DC character Agent Liberty — and an unexpected reveal for Supergirl herself! #WBSDCC #SDCC2018 (© 2018 Warner Bros. Entertainment Inc. All Rights Reserved.)