CSI Alina Burroughs is in Winter Garden, Florida, to investigate a furniture store massacre of four people by William Thomas "Tommy" Zeigler Jr. , age 34 at the time of the murders on Christmas Eve 1975. Applying new technology to old clues, Alina tries to piece together a puzzle still fraught with mystery. Zeigler was charged for the quadruple murder of his wife, Eunice Zeigler, and her parents, Perry and Virginia Edwards, as well as a customer named Charlie Mays. The furniture store was family-owned by the Zeigler family. Zeigler was convicted and sentenced to death in 1976. Due to years of legal maneuvering, Zeigler is alive and still in prison.