Adrian Chiles and Nadia Sawalha present a magazine series which includes a mix of interviews, topical reports and features from around the UK. There's the launch of the 16-60 Challenge to find out who's fittest - today's couch potato teenagers or their health-conscious elders. Dan Snow begins a series of reports about the UK's hidden history by donning a wet suit and diving into the chilly waters of Loch Tay to reveal the remnants of a strange Iron Age settlement.