Each week, host Alex Weber joins your favorite ninjas like Kacy Catanzaro, Geoff Britten, Ryan Stratis and more to get an insider's look at how an obstacle goes from an idea to the ultimate athletic challenge in Crashing the Course. And watch your favorite ninjas like Natalie Duran, Grant McCartney and more to see how they prime for competition in the weekly series 24/B4. Watch both NBC exclusive series on NBC.com and the NBC app.
