Theodore L. Gunderson (November 7, 1928 – July 31, 2011) was a Federal Bureau of Investigation Special Agent In Charge and head of the Los Angeles FBI,[1] an American author, and a conspiracy theorist.

In 1980, he became a defense investigator for Green Beret doctor Jeffrey R. MacDonald, who had been convicted of the 1970 murders of his pregnant wife and two daughters.

Gunderson obtained affidavits from Helena Stoeckley confessing to her involvement in the murders which she claimed had in actuality been perpetrated by a Satanic cult of which she was a member.

[16][17] He made numerous confident statements supporting the truth of the supposed abuse ring[18] and became a "recognized spokesman on the dangers of satanic ritual cults".

[20] Gunderson also claimed that in the United States, there is a secret widespread network of groups who kidnap children and infants and subject them to ritual abuse and subsequent human sacrifice.

[24][25][26] He was also an architect of conspiracy theories around the Oklahoma City bombing, promoting a narrative of an FBI coverup, and the idea that if McVeigh was one of the bombers then it was due to secret government mind control.

Instead, Gunderson alleged that top officials linked to an international drug and weapons ring feared the singer-turned-politician was about to expose their crimes, so they had Bono murdered on the ski slopes and staged the accident.