Clark (Tom Welling) returns to Smallville re-programmed as Kal-El. Intent on fulfilling his destiny, Kal-El takes to the skies to steal a powerful kryptonite crystal. Determined to save her son, Martha (Annette O'Toole) turns to Dr. Swann's emissary, Bridgette Crosby (Margot Kidder, Superman), and learns about a surprising new form of kryptonite. Meanwhile, Lois Lane (Erica Durance) comes to town to investigate the murder of her cousin Chloe (Allison Mack). Also, Lana (Kristin Kreuk) returns from Paris with a new attitude and a new boyfriend (Jensen Ackles, Dark Angel), Jonathan (John Schneider) lies in a coma, and Lionel (John Glover) faces a grim new life in prison.