It's 20 years since Buffy Summers first took her stakes into high school. So come and test your geek knowledge of the 90s, the noughties and the occult. Basically the best of everything, then. Both a popular American smash and a cult classic, inspiring reams of books and academic studies, Joss Whedon's breakout teen drama was a forerunner of today's so-called Golden Age of TV. Come and test your wits!