Orphan X by Gregg Hurwitz (Orphan X #1)

Evan Smoak is a man with skills, resources, and a personal mission to help those with nowhere else to turn. He was raised and trained as part of the Orphan program, designed to create perfect assassins. He was Orphan X. Evan broke with the program, using everything he learned to disappear. Now, however, someone is on his tail. Someone with similar skills and training. Someone who is getting closer and closer.

Recommended by Mr. Halacy, History Teacher: “Great book in the first of a series about an assassin with a conscience. He goes ‘off the grid’ and now helps people less fortunate as the ‘Nowhere Man.’"