Sorry

Four childhood friends, leaving their 20s and out of luck. Kris just got fired; he'll never be a journalist now. Tamara never had a steady job, and she's just given custody of her daughter to her former lover. Wolf's girlfriend has died of an overdose. Frauke's mother has been put in an asylum and she's freaked. They're a disaffected bunch of losers, going nowhere.
Then during one reckless drunken evening, they come up with a joke of an idea. Everyone in the world--large corporations, businessmen, lovers--behaves shittily to someone, and rarely do they apologise. The friends decide to set up an agency that, for a flat fee, does the apologising and makes things right. The agency, which they call Sorry, becomes a runaway success. Sorry visits injured party after injured party and offers the right apology, along with financial compensation. Soon the four former down-and-outs are living almost like millionaires in a beautiful old large villa looking out over Berlin's Wannsee River. But all of this comes to a screeching halt on the day Wolf goes to an apartment on the instructions of a new client. Seeing the door ajar, Wolf walks in and finds a woman hanging from a wall, with one nail driven through her hands and one through her forehead.
What follows is a sequence of events--kidnapping, torture, more deaths--that gradually declare themselves as a bewildering and intensifying psychological game of cat-and-mouse. After reading the shattering climax of this book, nobody will ever say 'Sorry' in quite the same way again.