The Limits of Pain — K. Arne Blom

He was being tortured - agonizingly tortured. All policemen make enemies, and Lieutenant Martin Holmberg was no exception. A number of men had sworn revenge, but he'd never feared them. Not until now. Now he and his family were being terrorized. Someone called his home every hour - but never spoke. Someone sent threatening cards to his wife. Someone promised to kill his children. But who? Holmberg knew the answer lay buried in his own past. Sometime during his career Martin Holmberg had tangled with a madman...a madman who had returned to destroy him. To destroy him completely.