Samantha has lived her whole life in different foster homes. Now living in a small town, she never feels like she quite fits in, even with her own current foster family who might adopt her, or the boy who follows her around doing her classwork. So, it’s perhaps natural that she doesn’t know what to do with a curious tagalong little sister named Olivia. One day, Sam callously ditches Olivia, who wanders off into the woods on her own and disappears.

After being struck by lightning, CSI investigator Barry Allen awakens from a nine-month coma to discover he has been granted the gift of super speed. Teaming up with S.T.A.R. Labs, Barry takes on the persona of The Flash, the Fastest Man Alive, to protect his city.

Thanks to his police officer father's efforts, Shawn Spencer spent his childhood developing a keen eye for detail (and a lasting dislike of his dad). Years later, Shawn's frequent tips to the police lead to him being falsely accused of a crime he solved. Now, Shawn has no choice but to use his abilities to perpetuate his cover story: psychic crime-solving powers, all the while dragging his best friend, his dad, and the police along for the ride.