Cold Justice (Mallory, Bk. 1)

Mallory - he was the best of the best, a Special Forces leader and a hero. But then he made a fatal decision, gambling with the lives of his men with terrible consequences: two dead, and his young friend Donno left in a coma.

Back on the streets, with nothing to lose, Mallory has a darkness growing inside him, a dangerous need to seek out trouble. Then Donno's mother asks him for help: her other son, Scott, has gone missing in South Africa, and she wants Mallory to find him.

Perhaps it's redemption, perhaps he's looking for revenge on the world, but suddenly Mallory has a purpose, and nothing and no one is going to stand in his way.