In 1960 MKULTRA had kidnapped 3 convicts who were all addicts and would do whatever there told if they were promised some drugs in the process.
Using that and "advanced interrgoation techniches" they created essisentally sleeper agents. However after the end of the coldwar it proved that there was no use for them.. Being they had no family memebers around they simply killed all of them. Except for one who escaped. Now later in modern day he comes to tell his story about the rights about of them and how they were effectively slaves who were tortured only to be hunted by CIA agents.