John Smith Versus the Nazis

So, I'm thinking of a cross between A History of Violence and Munich. A former Nazi SS guard hiding out in the USA and living "off the grid" is in the 1960s tracked down by Mossad agents who threaten to murder his entire family if he doesn't cooperate with their infiltration of a camp in South America run by former Nazis. Now, this guy committed crimes during WWII, but he was no Mengele-- just a young kid confused and brainwashed by the insanity that was Nazi Germany. He escaped to America and is haunted by the brutal things he saw and participated in. The Nazis in South America ,however, are the real thing-- evil fucks who have zero regrets about what happened in the 1940s and would give anything to see a return to those days.

The Mossad want these guys brought to justice-- they know the unit exists, but who the membership is and what they're planning is unknown. Plus, they're bring protected by the dictator of this South American country, who's more or less blackmailed them into running his own mini-concentration camps and training facilities. So, being a former Nazi (and probably knowing a few of these guys), he's forced by Mossad to figure these guys out.

I figure there's some other threads that could be thrown in. The CIA would need to be involved, one would think, and probably the KGB. Maybe the Nazis could be working on cloning Hitler or something. Or they've discovered a baby black hole and are leeching supernatural power off it. Or some geo-political stuff, I'm sure that'd be interesting.