Red Pill by Hari Kunzru

A writer has left his family in Brooklyn for a three month residency at the Deuter Centre in Berlin, hoping for undisturbed days devoted to artistic absorption. When nothing goes according to plan, he finds himself holed up in his room watching Blue Lives, a violent cop show with a bleak and merciless worldview. One night at a party he meets Anton, the charismatic creator of the show, and strikes up a conversation.
 
It is a conversation that leads him on a journey into the heart of moral darkness. A conversation that threatens to destroy everything he holds most dear, including his own mind.