The world is awash in deepfakes - video, audio or pictures in which people appear to do or say things they didn’t, or be somewhere they weren’t. Most deepfakes are explicit videos and images concocted by mapping the face of a celebrity onto the body of someone else. Some are used to scam consumers, or to damage the reputations of politicians and other people in the public eye. Advances in artificial intelligence mean it takes just a few taps on a keyboard to conjure them up. Alarmed governments are looking for ways to fight back.