Synopsis for
"Smallville" Arctic (2008)

Kara (Laura Vandervoort) tells Lex (Michael Rosenbaum) he is destined to defeat the Traveler and offers to take him to the Fortress to learn how.

Clark (Tom Welling) is stunned that Kara would go to Lex but it is revealed that Brainiac is impersonating Kara and she's actually trapped in the Phantom Zone.

Chloe is arrested by the Department of Domestic Security and Lana awakens from her comatose state.

Meanwhile, in an epic turn of events, Clark and Lex face off in the Fortress and Lex learns Clark's secret.

Kara suspiciously persuades Lex to travel to the Arctic with the knowledge that the cube-like object created by Kryptonians will protect him. Clark discovers that BrainIAC was in fact personifying his cousin, and Kara is really trapped in the Phantom Zone, a place where he once occupied for a short while. Once BrainIAC sends his best friend Chloe into a comatose state, he makes a confrontation with perhaps his most difficult foe. However, a quickly-becoming greater foe in his former friend, Lex, discovers that the Traveler is in fact Clark.