Tess Mercer

Smallville is an American television series developed by writer/producers Alfred Gough and Miles Millar, and was initially broadcast by The WB. After its fifth season, the WB and UPN merged to form The CW, which was the second broadcaster for the show in the United States. The series features a regular cast of characters, which began with eight main characters in its first season. Since then, characters from that first season have left the series, with new main characters having been both written in and out of the series. In addition, Smallville features guest stars each week, as well as recurring guests that take part in mini story arcs that span a portion of a season. Occasionally, the recurring guest storylines will span multiple seasons.

The plot follows a young Clark Kent, in the fictional town of Smallville, Kansas, as he journeys toward becoming Superman. Additionally, the series chronicles Lex Luthor's path to the dark side, and his metamorphosis from Clark's best friend to greatest enemy. Smallville depicts the relationship between Clark and his first love interest, Lana Lang, as well as his relationship with Lois Lane, the woman he ultimately marries in the comic books. The series also features recurring appearances from other DC Universe characters, such as Arthur Curry and John Jones.

With five months devoted to casting for the pilot, Gough and Miller cast ultimately hired eight actors to take on the role of series regulars for the first season. Since then, only two characters from the first season have remained regulars through to the eighth season, with seven new actors taking on lead roles from seasons two through eight. Four of those new actors began as recurring guests in their first seasonal appearance, but were given top billing the following season. As the series progresses, recurring guests appear at various times to help move the overall storyline of the show or just provide a side-story arc for one of the main characters, such as Brainiac or Adam Knight. Other recurring guests appear as background characters, showing up for only a few scenes, which includes characters like Sheriff Nancy Adams or Dr. Virgil Swann.

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