Keeley Donovan explores the hidden dangers of hillwalking and investigates whether we might be pushing ourselves too far in the search for a bit of fresh air. Steve Brown is shedding light on why one corner of Kent has become home to some stowaways with a sting in their tail. Margherita Taylor finds out how one childhood favourite could turn out to be the stuff of nightmares as an invasive species of ladybird arrives in the UK in swarms.