At the beginning of the first episode of the first season Penn pointed out that the series would contain more obscenity and profanity than one would expect in a series dealing with scientific and critical inquiry, but explained that this was a legal tactic because, “if one calls people liars and quacks one can be sued…but ‘assholes’ is pretty safe. If we said it was all scams we could also be in trouble, but ‘bullshit,’ oddly, is safe. So forgive all the ‘bullshit language’, but we’re trying to talk about the truth without spending the rest of our lives in court.”
Paranormal subjects of episodes include alien abduction, alternative medicine, literal exegesis of the Bible, and ESP. Other episodes cover social issues such as the War on Drugs, organic food, animal rights, gun control, and environmentalism. Penn & Teller approach the topics in the manner of Harry Houdini and James Randi (who has appeared more than once on the show), who are known for debunking claims of supernatural powers.
The show began airing its eighth season on June 10, 2010. As of its seventh season, it became Showtime’s longest running series. The series has achieved worldwide success, being shown in countries such as Argentina, Australia, Bosnia and Herzegovina, Brazil, Canada, Colombia, Denmark, Finland, Iceland, Mexico, New Zealand,Norway, Ireland, Sweden, Venezuela and the United Kingdom.