Why Lauren Lee Smith's Riley Left CSI After Season 9

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Lauren Lee Smith was introduced on CSI: Crime Scene Investigation as the crime lab's newest addition, Riley Adams, but exited the series shortly thereafter. Starting her stint with CSI season 9, episode 3, «Art Imitates Life,» she was quickly written out at the end of the same season, with very little fanfare. Originally seen as a replacement for the outgoing character of Sara Sidle, Riley Adams's disappearance from the series barely left a mark. Still, some may have questioned why the character was written out after only one season. Unfortunately, many didn't think she was an adequate replacement for Sara Sidle, and Lauren Lee Smith exited the series.

Lauren Lee Smith was a series regular, but her character resigned from the crime lab in CSI's season 9 finale,  and wasn't seen on the series again. In CSI season 10, episode 1, «Family Affair,» Catherine Willows discovered a report that was written by Riley detailing how ineffective Catherine's leadership was and that she had accepted a different position in the Midwest. Catherine was seen wondering if Riley's comments were correct and if her leadership of the CSI team needed some fine-tuning.

Related: CSI Needs to Address Catherine's FBI Years (& Why They Ended)

While Riley's resignation came swiftly, the character was eventually written off the series after CSI season 9 because Lauren Lee Smith never seemed to fit with the cast. Smith apparently left because she "didn't find a balance in the ensemble" (via Cinema Blend). Offscreen, Smith wasn't a good match for the series, especially after the departures of original series regulars Jorja Fox and Gary Dourdan. Gary Dourdan's Warrick exited CSI in season 9, and the creators might have realized that major cast changes were