The tenth season of CSI: Crime Scene Investigation premiered on CBS on September 24, 2009, and ended May 20, 2010.

The team, including the newly returned Sara Sidle, continue to investigate the gruesome, the premeditated, and the unusual, including the death of a porn producer ("Ghost Town"), a botched robbery ("Working Stiffs"), a cop-on-cop homicide ("Coup de Grace"), the murder of a football coach ("Blood Sport"), a bizarre revenge plot ("Death & The Maiden"), a death at a bowling tournament ("Lover's Lanes"), and a human trafficking case that leads Ray to both New York and Miami ("The Lost Girls").

Meanwhile, Nick, Greg, and Hodges celebrate Henry's birthday ("Appendicitement") as Catherine comes face to face with Rascal Flatts ("Unshockable"), and Langston begins to investigate a series of murders committed by Dr. Jekyll ("Sin City Blue"), which may lead to his own brutal end ("Meat Jekyll").

And at the end, Ray and Dr. Robbins find something unusual in a body of a street performer.

Ray searches for a missing girl being held hostage by human traffickers.