This smug, chatty Brit is exactly the mischief I didn't know my inbox was missing. She's eighteen, but don't let the sweet teen-act fool anyone, her content plays sly and sharp, equal parts bratty ...

As Mr Doodle, Sam Cox found a global audience and made a fortune with his signature scrawls covering furniture, clothes – and eventually an entire house. But behind the scenes, he was unravelling into ...