What connects amateur sleuths turning up at crime scenes, anti-social behaviour in UK schools and riots in France? The answer, according to a BBC investigation, is that they are all examples of a TikTok 'frenzy'. Marianna Spring, the BBC’s disinformation correspondent, has spent the last year investigating harmful behaviour on TikTok spilling out into the real-world. She tracks down users, victims and former employees to expose how extremely high engagement on TikTok around some topics appears to be creating these 'frenzies' linked to behaviour previously seen as unacceptable.