Warning signs of the instability of the global financial system abounded in the months leading up to the 2008 Lehman Brothers crash. Among these early signs were the astounding revelations about UBS, the world’s largest private bank, by Stephanie Gibaud, who was employee at the bank’s French division. Gibaud refused instructions given to her and other employees to delete all their company files. In doing so, she helped reveal a vast web of corruption and fraud linking UBS to a shadowy tax