Dakota Chase continues her young adult series, Repeating History, with Hammer of the Witch, returning to a contemporary world featuring magical, time-traveling shenanigans surrounding two teenagers. To recap: In the first novel, The Eye of Ra, we met up with Aston and Grant at an unfortunate time in their lives.  After a visit to juvenile court both boys are sentenced to a year at the Stanton Boys School, where their shenanigans intertwine after an incident in their history teacher’s office (which they manage to set fire to, destroying several priceless artifacts housed within).  And it just so happens that their history teacher is the esteemed wizard Merlin.  He-who-ran-with-King-Arthur, Merlin.  Why the man would want to teach high schoolers is beyond me, but maybe he enjoys it.  Aston and Grant have never been in this much trouble before, but an unlikely solution is found when they are tasked with going back in time and retrieving some of these artifacts for Merlin.  In the first book Aston and Grant traveled back to Ancient Egypt in the times of King Tut, but the second book sends them back to medieval Europe, in the midst of the witch hunts.