Chris Hardwick, comic Jordan Carlos and scientist Bob Pflugfelder discuss history's worst medical advice.

Courtney Cox, comedian Dan Soder and author/comedian Michael Ian Black debate and discuss history's biggest frenemies.

Guests Elijah Wood, comedian Bryan Callen and Professor Dan Schnur discuss history's most doomed presidential campaign.

Julie Bowen, Dan Levy and Laila Lalami discuss the worst tyrants in history.

Jack Black, Tymberlee Hill and Stephen Prothero talk about crazy cults.

Trace Adkins, Kate Flannery and Lori Greiner talk about great inventions of the past half century.

Lars Ulrich, Tom Papa and Alan Light talk about great rock bands,

David Eisenbach, Maria Bello and Derek Waters talk medicine.

Jay Leno, Mark Forward and Howard Bragman

Adam Goldberg, Noel Wells and Ty Pennington talk great modern mysteries

Judd Apatow, Kurt Braunohler and Mike Massimino don tin foil hats.

Angela Kinsey, Heather McDonald and Joel Stein talk bad boy presidents.

Dan Riskin, Ian Abramson and Tim Meadows talk about the dumbest mistakes in history.

Michael Ian Black, Josh Wolf and Jason Biggs channel Robert Stack for a look at famous unsolved mysteries.

Derrick Pitts, Thomas Dale and Joel McHale talk about the greatest gangsters to ever have lived.

Mike Massimino, Megan Amram and Larry King talk about the greatest known unexplained phenomena.

John Avlon, Yvette Nicole Brown and Lisa Kudrow talk about big mmoments where people still revolt.

Joel Stein, Jo Koy and Fred Willard discuss the founding fathers.

Joel Stein, Russell Peters and Michael Sheen talk about history's frauds.

Evy Poumpouras, Mark Forward and Regis Philbin talk about the badasses of history.