Smallville III (18/22)

When Chloe accidentally inhales a mysterious gas, she discovers that it gives her the ability to get the truth from anyone who comes in contact with her--and she goes to the Kents to find out Clark's secret. However, her new power is not without its consequences, and Clark must find an antidote before she discovers too much about him or, worse, dies.

Tom Welling, Michael Rosenbaum, Allison Mack, Kristin Kreuk, Annette O'Toole, John Schneider