S.M.E.R.S.H. (short for Smert' Shpionam, or "Death to Spies") was a counterintelligence department in the Soviet Union formed during World War II. His function was to secure the rear of the active Red Army on the front and to arrest "traitors, deserters, spies, and criminal elements". S.M.E.R.S.H. was allowed to investigate whomever it wished even in the highest state bodies. It was often sent out to find and kill defectors, double agents, etc. S.M.E.R.S.H. activities included "filtering" the soldiers recovered from captivity.