Jensen Ackles has been added to the cast of the WB Network drama "Smallville" as a regular. He will play the stubbornly independent heir to a rich Metropolis financial firm who becomes romantically involved with Lana Lang (Kristin Kreuk). Ackles, who recently completed filming on his first starring feature, "Devour," co-starred on such series as Fox's "Dark Angel" and "Still Life" and the WB's "Dawson's Creek." He is repped by WMA and Lainie Stolhanske.