In this week's episode, Benton and Anna take a look at some of our more modern investigative tools and the history behind them, as well as some cases involving very unusual evidence.  First, Benton takes a look at the Bertillon method for identifying offenders and the remarkable case of William and Will West.  Then, Anna gives a rundown of the tragic case of Jessica Chapman and Holly Wells, whose murders were solved by the work of a botanist.  Finally, the two discuss the murder of Deputy Bill Simmons in Illinois that was solved by putting a witness under hypnosis.

Our TV doc this week is the second segment of Season 1: Episode 16 of Cold Case Files, "The Tow Truck Killer".