Heather Doerksen

In the second of a two-part season finale, sacrifices will be made and both universes may never be the same again after Walter and Olivia visit the "other side."

The intensity of life “over there” accelerates as Olivia finds herself in mortal danger.

The beginning of the end is triggered when Walternate finds a way to wreak havoc “over here” – putting both universes in jeopardy.

Kevin Grady (Jonathan Bennett - "Mean Girls," "All My Children") possesses the ability to make people lose their memories. Kevin unleashes his power on Clark, causing him to suffer total amnesia. Chloe discovers Clark's malady and teaches him about his superpowers--while simultaneously trying to keep Clark from accidentally revealing his powers to others. Consequently, Clark meets Lana, becomes enamored of her and decides to share his secret with her. Seizing the perfect opportunity, Lex tries to convince Clark to show him where the three stones are hidden.

Clark discovers the reason Lana married Lex then and sets out to kill Lionel. Lex tries to use DNA from the last phantom to power his super-soldiers. Lois goes to a dam to search for Lex's lab but is caught by a security guard and fatally injured. Chloe's power is discovered.