Real, Fake or Unknown

Three death-defying videos are under the microscope. A hoverboarder teeters high above Dubai. A man dices with death under a train. A snowboarder has a grizzly encounter with a bear. Are they real?

This episode puts some of the web's most-watched animal clips under the microscope, including extreme shepherding, a vengeful lion and a cradle-snatching eagle. Are they real?

Proving the authenticity of internet promotional videos, featuring a European video advertising a new extreme sport and a commercial for a jet-powered hoverboard

Experts try to prove the authenticity of internet clips showing people's amazing talents, from ocean-surfing motorbiking in Tahiti to a Spanish game of skydiving catch

This episode investigates illusions. Can spinning an upturned glass of water really make it defy gravity? Did a performance group play a deadly game of ping pong with kitchen knives? Is a clip that shows the ground liquefying real? Can a subwoofer sound system pump out bass so powerful that it turns a car to jelly? Are these clips real or fake?

Some viral clips grab headlines around the world, but that doesn't mean they're all real. A futuristic head shave that threatens every barber shop on the planet, an apparently superhuman remote helicopter, the world's most idiotic selfie and a city in the sky are in the spotlight in this episode. Are these clips real or fake?