The Vanished Man (Lincoln Rhyme #5) by Jeffery Deaver

It begins at a prestigious music school in New York City. A killer flees the scene of a homicide and locks himself in a classroom. Within minutes, the police have him surrounded. When a scream rings out, followed by a gunshot, they break down the door. The room is empty.

Lincoln Rhyme and Amelia Sachs are brought in to help with the high-profile investigation and to ferret out a master illusionist they've dubbed "the conjurer." As the fatalities rise and the minutes tick down, Rhyme and Sachs must move beyond the smoke and mirrors to prevent a terrifying act of vengeance that could become the greatest vanishing act of all.