Flash, The: S4 (Blu-ray)Last season, Barry Allen aka The Flash (Grant Gustin) used his extraordinary abilities to travel back in time and save his mother’s life, and inadvertently created an alternate timeline known as Flashpoint. The phenomenon not only gave birth to the villainous God of Speed known as Savitar, but changed the lives of Caitlin Snow (Danielle Panabaker) and Wally West (Keiynan Lonsdale) forever. With the help of his adoptive father, Detective Joe West (Jesse L. Martin), his fiancée Iris West (Candice Patton), and his friends at S.T.A.R. Labs – Cisco Ramon (Carlos Valdes) and Harrison Wells (Tom Cavanaugh) -- Barry continues to protect the people of Central City from the meta-humans that threaten it. But first, he’ll have to escape the Speed Force – an extra-dimensional entity teeming with unknown dangers – that Barry sacrificed himself to in order to save Central City.