Sam West and Adrian Edmondson visit the flooded Somerset Levels in search of a bittern, Britain's loudest - and possibly most mysterious - bird. At RSPB Ham Wall, the search for the bittern is proving tricky, but they're rewarded by a pair of Great Crested Grebes who put on a dazzling display for them both. While talking hobbies, Adrian confides in Sam about the real reason he needs to keep busy.