Never have I had to be cautious not to write spoilers into a review for a history book. But Mr. Collier's Letter Racks is the historical equivalent of a thriller. The book revolves around illusionist trompe l'oeuil paintings produced by a Dutch artist, Edward Collier, who shared his time between Holland and England in the late seventeenth century. The letter racks in the title were boards with straps of leather pinned on them that were used to hold letters, newspapers, pamphlets, portrait medallions, and implements such as wax, quills, and combs. The paintings were a refinement on vanitas compositions, themselves a product of the earlier, seventeenth-century Dutch vogue for still lives. Dror Wahrman uses them to make fascinating points about the revolution in media that was taking place at the time, about Anglo-Dutch dynastic politics, and about the professionalization of art. But Collier was playing games within games within other games. There are parallels with the modern media revolution of the internet, indeed, which the author does not hesitate to make. But Wahrman's role is none other than that of the detective, tracking hidden date changes, signatures concealed within objects, intentional misspellings, fake titles and escutcheons, etc. and collating it all with real archival material in order to find out who was who or could have met with whom. And the greatest bombshell, meanwhile, comes only at the very end, in the epilogue. On the face of it a book about an odd subject, this is actually a captivating read as well as, in the data and detail the author has managed to dig up, an extraordinary feat of scholarship.