Two guys. 19 experiments. Five continents. 91,000 miles. And a book that will forever change the way you think about humor.

Part road-trip comedy and part social science experiment, a scientist and a journalist detail their epic quest to discover the secret behind what makes things funny.

Dr. Peter McGraw, founder of the Humor Research Lab at the University of Colorado Boulder, teamed up with journalist Joel Warner on a far-reaching search for the secret behind humor. Their journey spanned the globe, from New York to Japan, from Palestine to the Amazon. Meanwhile, the duo conducted their own humor experiments along the way—to wince-worthy, hilarious, and illuminating results.

In their quixotic search, they questioned countless experts, from comedians like Louis C.K. to rat-tickling researchers, and answered pressing (and not-so-pressing) questions such as, “What’s the secret to winning The New Yorker cartoon caption contest?”; “Who has the bigger funny bone—men or women, Democrats or Republicans?”; and “Is laughter really the best medicine?” As a final test, McGraw uses everything they learned to attempt stand-up—at the largest comedy festival in the world.

Funny, surprising, and often touching, The Humor Code is a revealing exploration of humor, society, and an unusual friendship.

Peter McGraw, a professor at the University of Colorado Boulder where he directs HuRL (the Humor Research Lab), is a leading expert in the interdisciplinary fields of emotion and behavioral economics. His work has been covered by NPR, Nightline, The Wall Street Journal, Scientific American, The New York Times and the BBC. He lives in Boulder, Colorado.

Joel Warner, an award-winning former staff writer for Westword, Denver’s alternative newsweekly, has written for Wired, The Boston Globe, Slate, Grantland, and other publications. He lives in Denver, Colorado.