We assume that the high-end artworks sold at auction are real, reputable and legal, but this isn't always the case. Looting and lies, forgery and theft – plus the odd stunt – all play their part in this world where the stakes are high and the profit margins huge. With a Tutankhamun bust selling in the millions recently, leading to an impending court case, and a sold Banksy stencil shredding in front of the auction house's eyes, we take a look at the most controversial and heavily criticised auctions around the globe.