An absolutely fascinating book - I remember starting it and being immediately fascinated by David's story. There's so much in this book which made me read with my mouth agape - it's a riveting mix of science and real stories of people's (including David's) struggles with OCD. Those without OCD don't tend to think of the trigger but more how it affects everyday life; the fact David detailed why his OCD came about really put things into perspective. The term OCD is thrown around quite casually sometimes but this book gives a greater depth of understanding as to how it affects people, and what the difference is between normal behaviours and mental illness.