Smallville (2001)

S3E19 Memoria

Convinced that crucial details about his father's history vanished with his erased memories, Lex opts to participate in a groundbreaking program run by Dr. Garner in hopes of retrieving that information to hand his father over to the FBI. Aware that Lex will uncover his secret if he succeeds, Clark attempts to intervene. However, he is intercepted by Lionel and the doctor, who subsequently subjects him to the same intense treatment in a bid to unravel the secrets of Clark's origins.