Sword of Damocles - Mark Reilly, #1

Absolution or Armageddon? Ex-Ranger Mark Reilly leads a troubled life. After parting with the US Army on less than amicable terms, he finds work as a gun-for-hire in the European underworld. The pay is good, and the work is steady, but Mark's enthusiasm sours when his employer branches out into child trafficking. Striking out on his own, Mark forms his own mercenary company with his ex-IRA girlfriend and a veteran from his old unit.
Their first job, rescuing two sisters from human traffickers, is a phenomenal success. However, soon after returning the girls to their parents, Mark and his friends find themselves kidnapped by his former Army CO, who now works for the CIA. Mark's CO gives him a more critical and urgent assignment: recover six stolen American nuclear warheads. Mark and his team are now in a race against time, utilizing all their contacts in the criminal underworld to find the nukes before they fall into dangerous hands.
The mission soon turns ugly when Mark is confronted by a former enemy. Will his lust for vengeance blind his judgment, putting the mission-and his friends-at risk?