Skinner had been shot in the previous episode. Agent Scully turned to Pendrell to help her find the guilty party. Pendrell analyses the saliva found on Skinner's shirt. Pendrell went on to perform a chromosome-stain on some hair fibers taken from the crime seen. Pendrell continues in this vein until he has not only single-handedly caught the man who shot Skinner but also go on to track down Melissa Scully's assassin.