Orhan Pamuk 
The Black Book 

As he investigates the mysterious disappearance of his wife and a popular newspaper columnist, Celâl, Galip finds himself assuming the enviable Celâl’s identity, wearing his clothes, answering his phone calls, even writing his columns. With its cascade of beguiling stories about Istanbul, The Black Book is a brilliantly unconventional mystery, and a provocative meditation on identity.