The world that surrounds the JFK assassination is, at baseline, so bizarre and so susceptible to any cockamamie idea that the news that the former president’s brain is missing seems like a standard news dispatch, a routine day at an office where alien abductions are greeted with a bored shrug.

But the claim that the First Brain was swiped not by the CIA or the Cubans or Marilyn Monroe but by Kennedy’s own brother, the former attorney general of the United States, Robert Kennedy, has gotten enough mainstream attention to merit a thorough debunking.

The story is this: in the book, End of Days: The Assassination of John F. Kennedy, author James Swanson reactivated the sleeper cells of JFK conspiracists—not a difficult task—with his incendiary claim that RFK had absconded with his brother’s brain. The reason, Swanson speculated, was not to keep people from learning the true truth about how many bullets, and from what angle, were shot at the president, but rather because RFK wanted to make certain the world didn’t find out the truth about JFK’s health.