Smallville: Season 4, Episode 20

4 - 20: Ageless

Clark and Lana discover an abandoned baby in the cornfield and take him back to the Kent farm. However, once the baby ages from a newborn to a 7-year-old in a matter of days, the two realize he is aging at a rapid rate and frantically search for a cure before the disease kills him. Meanwhile, Genevieve orders Lionel to kill Lana or else she will send him back to prison...