Ruth is a beautiful, intelligent teacher and singer from east London and she lives with Tourette syndrome. The emergence of tics and rude outbursts caused her to quit a music course at university some years ago and now she is ready to try singing again, the one thing that banishes her symptoms. But there's no X Factor-style sob story or false jeopardy needed with Ruth's clear-eyed perspective and mature delivery. The moment she explains her "neurological disorder" to a disapproving man in the supermarket is ovation-worthy. Another brilliant BBC3 documentary. What is going on? Julia Raeside