Follows six extreme sports stars as they prepare for and then compete in the 2008 Summer X-Games in Los Angeles. Kyle Loza practices a new motocross trick, landing in a pit of foam. Can he do it in front of thousands and land safely on dirt? Travis Pastrana shifts from a bike to a rally car - in part because he's broken so many bones. Shaun White finishes his snowboard season and jumps immediately onto his skateboard. Retired motocross champion Ricky Cunningham takes up a new event. In the finale, after practicing together as friends and competitors, Bob Burnquist and Danny Way face off on the mega ramp

Superstar scientists Marty Blaser and Gloria Dominguez-Bello - passionate partners in life and in the lab- show us how overuse of antibiotics and elective C-sections are destroying the healthy bacteria in our bodies, and fueling the stratospheric rise in obesity, diabetes, asthma, and food allergies. Our dynamic duo is on a mission to protect and restore our missing microbes before it's too late.