Smallville V (7/22)

Clark is exposed to silver kryptonite, causing him to have paranoid delusions. The element makes him believe that Chloe is going to reveal his secret; Jonathan is scheming against him with Lionel; and Lex and Lana are having a secret relationship. Chloe and the Kents frantically search for a cure; however, it is Professor Fine (recurring guest star JAMES MARSTERS) who comes to Clark's rescue--but not without his own agenda.

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