David Morris Aaronovitch is an English journalist, television presenter and author. He is a regular columnist for The Times and the author of Paddling to Jerusalem: An Aquatic Tour of Our Small Country (2000), Voodoo Histories: the role of Conspiracy Theory in Modern History (2009) and Party Animals: My Family and Other Communists (2016). He won the Orwell Prize for political journalism in 2001, and the What the Papers Say "Columnist of the Year" award for 2003. He previously wrote for The Independent and The Guardian.

Hugh Grant Aynesworth is an American journalist, investigative reporter, author, and teacher. Aynesworth has been reported to have witnessed the assassination of John F. Kennedy in Dealey Plaza, the capture and arrest of Lee Harvey Oswald at the Texas Theater, and the shooting of Oswald by Jack Ruby in the basement of the Dallas Police Headquarters. In a 1976 Texas Monthly article, William Broyles, Jr. described Aynesworth as "one of the most respected authorities on the assassination of John F. Kennedy".

Michael Barkun is an American academic who serves as Professor Emeritus of political science at the Maxwell School of Citizenship and Public Affairs, Syracuse University, specializing in political and religious extremism and the relationship between religion and violence. He has authored a number of books on the subject, including Religion and the Racist Right: The Origins of the Christian Identity Movement (1996), A Culture of Conspiracy: Apocalyptic Visions in Contemporary America (2003), and Chasing Phantoms: Reality, Imagination, and Homeland Security Since 9/11 (2011).

John Foster "Chip" Berlet is an American investigative journalist, research analyst, photojournalist, scholar, and activist specializing in the study of extreme right-wing movements in the United States. He also studies the spread of conspiracy theories. Since the 1995 Oklahoma City bombing, Berlet has regularly appeared in the media to discuss extremist news stories. He was a senior analyst at Political Research Associates (PRA), a non-profit group that tracks right-wing networks.

Vincent T. Bugliosi Jr. was an American attorney and New York Times bestselling author. During his eight years in the Los Angeles County District Attorney's Office, he successfully prosecuted 105 out of 106 felony jury trials, which included 21 murder convictions. He was best known for prosecuting Charles Manson and other defendants accused of the Tate–LaBianca murders of August 9–10, 1969.

Avram Noam Chomsky is an American linguist, philosopher, cognitive scientist, historian, social critic, and political activist. Sometimes called "the father of modern linguistics", Chomsky is also a major figure in analytic philosophy and one of the founders of the field of cognitive science. He is Laureate Professor of Linguistics at the University of Arizona and Institute Professor Emeritus at the Massachusetts Institute of Technology (MIT), and is the author of more than 150 books on topics such as linguistics, war, politics, and mass media. Ideologically, he aligns with anarcho-syndicalism and libertarian socialism.

Richard Dawkins is a British evolutionary biologist and author. He is an emeritus fellow of New College, Oxford and was Professor for Public Understanding of Science in the University of Oxford from 1995 to 2008. An atheist, he is well known for his criticism of creationism and intelligent design.

Ben Goertzel is an artificial intelligence researcher, and CEO and founder of SingularityNET.

Nidhal Guessoum M.Sc, P.hD. is an Algerian astrophysicist. He is a professor at the American University of Sharjah, United Arab Emirates.

Samuel Benjamin Harris is an American philosopher, neuroscientist, author, and podcast host. His work touches on a wide range of topics, including rationality, religion, ethics, free will, neuroscience, meditation, psychedelics, philosophy of mind, politics, terrorism, and artificial intelligence. Harris came to prominence for his criticism of religion, and Islam in particular, and is known as one of the "Four Horsemen" of New Atheism, along with Richard Dawkins, Christopher Hitchens, and Daniel Dennett.

Thomas Carl Hartmann is an American radio personality, author, former psychotherapist, businessman, and progressive political commentator. Hartmann has been hosting a nationally syndicated radio show, The Thom Hartmann Program, since 2003 and hosted a nightly television show, The Big Picture, between 2010 and 2017.

William Maher is an American comedian, actor, political commentator, and television host. He is known for the HBO political talk show Real Time with Bill Maher (2003–present) and the similar late-night show called Politically Incorrect (1993–2002), originally on Comedy Central and later on ABC.

Alan Moore is an English writer known primarily for his work in comic books including Watchmen, V for Vendetta, The Ballad of Halo Jones, Swamp Thing, Batman: The Killing Joke and From Hell. Regarded by many as the best comics writer in the English language, he is widely recognized among his peers and critics. He has occasionally used such pseudonyms as Curt Vile, Jill de Ray, Brilburn Logue, and Translucia Baboon; also, reprints of some of his work have been credited to The Original Writer when Moore requested that his name be removed.

Joe Nickell is an American skeptic and investigator of the paranormal.

Philip Cary Plait, also known as The Bad Astronomer, is an American astronomer, skeptic, writer and popular science blogger. Plait has worked as part of the Hubble Space Telescope team, images and spectra of astronomical objects, as well as engaging in public outreach advocacy for NASA missions. He has written two books, Bad Astronomy and Death from the Skies. He has also appeared in several science documentaries, including How the Universe Works on the Discovery Channel. From August 2008 through 2009, he served as president of the James Randi Educational Foundation. Additionally, he wrote and hosted episodes of Crash Course Astronomy, which aired its last episode in 2016.

Gerald Leo Posner is an American investigative journalist and author of thirteen books, including Case Closed: Lee Harvey Oswald and the Assassination of JFK (1993), which explores the John F. Kennedy assassination, and Killing the Dream: James Earl Ray and the Assassination of Martin Luther King, Jr. (1998), about the assassination of Martin Luther King, Jr. A plagiarism scandal involving articles that Posner wrote for The Daily Beast and his book Miami Babylon arose in 2010. In 2015, the Chicago Tribune called Posner "a merciless pitbull of an investigator."

Cass Robert Sunstein is an American legal scholar known for his studies of constitutional law, administrative law, environmental law, and law and behavioral economics. He is also The New York Times best-selling author of The World According to Star Wars (2016) and Nudge (2008). He was the Administrator of the White House Office of Information and Regulatory Affairs in the Obama administration from 2009 to 2012.

Mick West is a British-American science writer, skeptical investigator, and retired video game programmer. He is the creator of the websites Contrail Science and Metabunk, and he investigates and debunks pseudoscientific claims and conspiracy theories such as chemtrails and UFOs. His first book is Escaping the Rabbit Hole: How to Debunk Conspiracy Theories Using Facts, Logic, and Respect.