Straightforward versions of the dramatic repertory are easy to come by in this town. Tights and tunics? Check. Modern-dress versions of the same soliloquies and swordplay? No problem. But there aren’t so many places where you can see the classics actually reconceived and reimagined. For large-scale, daring interpretations of great dramas, Brooklyn Academy of Music is the spot. Bold directors with decent budgets and visual imaginations are the key here. So is a pair of grand old theaters exuding old-world atmosphere. From Annie Dorsen’s computer-algorithm A Piece of Work: A machine-made Hamlet to Thomas Ostermeier’s breathtaking political version of Ibsen’s An Enemy of the People, BAM offers us directors who dust off old dramas and challenge us to ask what they might really mean today.