Eobard Thawne--Reverse-Flash--kidnaps Dr. McGee and forces her to find a way to send him back to his own time. Flash and his friends discover that Reverse-Flash is from a timeline before he killed Barry's mother, and realize that they may have no choice but to send him back. Meanwhile, Harry and Cisco work to stabilize Cisco's vibe power, and Caitlin desperately tries to find a cure for Jay's illness.