Clark falls headlong into a cave, where he finds a beautiful girl and a wall inscription with the key to his origins.
When Lex's thugs hold Lionel and Martha hostage, Clark tries to mount a rescue by making a leap to a tall building with a single bound without revealing his powers.
When Lionel is shot in the manor, Jonathan is arrested. Clark and Pete suspect that others, including Lex, may be involved, and try to find out who pulled the trigger.
A woman claims to be Clark's mother, prompting the Kents to reveal what happened the fateful day they found their adopted son in a cornfield.
Castle and Beckett find themselves in flashback mode to the 1940s.