The Flash 3×19 “The Once and Future Flash” Season 3 Episode 19 Sneak Peek – TOM CAVANAGH DIRECTS; BARRY TRAVELS TO THE FUTURE TO SAVE IRIS – Barry (Grant Gustin) travels to the future to find out Savitar’s still unknown identity in the hopes of saving Iris (Candice Patton). Upon his arrival in 2024, Barry encounters future versions of his Team Flash friends, who, following the death of Iris, have become very different people, profoundly impacted by their showdown with Savitar. It will be up to Barry to infuse a sense of hope back into the team, as he proves to be hero his future friends have been waiting for. Meanwhile, back in 2017, the hunt for Killer Frost (Danielle Panabaker) continues. Tom Cavanagh directed the episode written by Carina Adly MacKenzie (#319). Original airdate 4/25/2017.