Kristin Kreuk’s Smallville character, Lana Lang, was the subject of a lot of hate from the fan community. Based on the comic book character of the same name, Lana was Clark Kent’s main love interest for most of the show’s 10-season run. Kreuk had second-billing behind Tom Welling through season 6, and remained a series regular until the end of season 7. But after a string of guest appearances in season 8, Lana’s time on Smallville came to an end.
Long before falling in love with Lois Lane (Erica Durance) in the later seasons, Clark’s attention was on Lana, who started out as the girl next door. For the first two seasons, Clark and Lana had a will-they-won’t-they dynamic. It evolved into an on-and-off relationship which was often complicated by Clark’s Kryptonian heritage and other incidents that occurred in their lives. Separate from Clark, Lana had several of her own stories on Smallville, including her relationship with her biological father in season 2 and the plotline with her ancestor Isabelle Thoreaux in season 4.
Lana had a strong presence on Smallville but wasn’t universally liked by the fans. The hatred toward Lana started early in the show’s lifetime, and a great deal of it had to do with Smallville's focus on her relationship drama with Clark. Many felt that the early seasons devoted too much time toward her, and how she treated Clark was a major point of contention as well. After spending half of season 3 waiting for Clark to resume their romance, Lana changed her mind because of Adam (Ian Somerhalder), and she chose to trust someone who she thought was Whitney (Eric Johnson) over Clark in season 2.
Lana’s trust issues with Clark persisted for several seasons, much to the frustration of some fans. What made this even worse was when her failed relationship with Clark led her to seek comfort from Lex (Michael Rosenbaum) in Smallville season 5. Lex then manipulated her into being with him instead. And Lana being completely sold on Lex’s lies in seasons 5 and 6 only worsened fans’ attitude toward her.
It’s important to point out, though, that a lot of the issues fans had with Lana stemmed more from Clark’s actions than they did hers, such as the impact she had on him. All Clark wanted in his high school years was to be with Lana; his love for her clouded his judgment in numerous episodes. Also, it’s worth noting that the continuous ups-and-downs of their romance occurred as a result of Clark not telling Lana his secret until the season 6 finale, and his repeated attempts to push her away and end their relationship. Because of Clark’s secrets, Lana’s loyalty faced several tests in the series. While there may be no excuse for Lana getting involved with Lex, Clark gave her plenty of reasons to have trust issues in Smallville.