The Assassination Bureau has existed for decades (perhaps centuries) until Diana Rigg begins to investigate it. The high moral standing of the Bureau (only killing those who deserve it) is called into question by her. She puts out a contract for the Bureau to assassinate its leader on the eve of World War I.
An American reporter smells a story when he is stranded in an Iron Curtain country where the local dictator is using gamma rays to transform children into mutated henchmen.