Fearne Cotton and Reggie Yates are sent on a roadtrip of a lifetime around the USA to discover the weird, wacky and wonderful things the US has to offer. It's week four and the city slickers continue their roadtrip round the USA, wandering way out in the Wild West of Arizona. They get back to basics with some horse herding and banjo bashing. Can they cut it as cowboys or will they buckle under?