MK Ultra is very real, and still ongoing to my understanding.
Bill Clinton admitted that radiation experiments, alongside a whole host of other things, were carried out by the American government on American citizens during the time of the cold war:
There are obvious ties to the eugenics program in the United States as well, which was basically an offshoot of the German eugenics program in WW2 that I covered in another thread:
Like eugenics, MK Ultra was basically an American continuation of what the Germans had started in WW2.
MK Ultra was publicly admitted by the American government but not before they tried to cover it up first by attempting to destroy all of the evidence (so who is to say it hasn't continued in a different guise?), this has also been admitted in mainstream sources (Wikipedia):
The very same people who tried to cover it up are also saying that they halted it
If those few documents had not survived the purge, MK Ultra would have gone down as just another 'conspiracy theory' in the history books.