: The central narrative shifts to the tragic deterioration of Clark and Lex’s friendship. Lex's obsession with Clark's secret leads him down a dark path, eventually resulting in him becoming Clark's greatest nemesis. The Fortress

Arguably the most emotionally devastating season. Jonathan Kent (John Schneider) dies of a heart attack, Clark gains his Fortress of Solitude, and Lex and Lana begin a relationship that fans love to hate. The season also introduces Brainiac and sets up the "Vessel" for Zod.

Smallville (2001–2011) follows the 10-year origin story of Clark Kent, adhering to a "no tights, no flights" rule until its finale. The series is often viewed in three distinct phases of quality and narrative focus. Phase 1: The High School Years (Seasons 1–4)