Call it the case of the missing cast member. “CSI” star Jorja Fox didn’t show up to film a pivotal cliff-hanger scene in LA on April 20 in which her character, Sara, is in a car wreck, claims an insider. “Producers were unable to find her,” claims an insider, adding that the scene had to be shot with a “blood-covered stand-in.” Jorja was fired - and quickly rehired - from “CSI” in 2004 when she held out for a pay increase right before the show’s fifth season. Could the actress be playing hardball again? While a set insider says Jorja was a no-show, her rep insists that she showed up for work that day: “She didn’t walk out for salary demands. Her contract is up and they’re in negotiations.”