Death and Honor by W.E.B. Griffin and William E. Butterworth IV

In 1943, with World War II at its peak, Argentina becomes a shadow battlefield for spies, traitors, and secret missions. OSS agent Cletus Frade is sent to Buenos Aires to uncover Nazi operations running through South America — and discovers a network of corruption that reaches deep into both Allied and Axis circles. As he fights to stop German agents from escaping with stolen gold and intelligence, betrayal strikes from within his own ranks. Death and Honor delivers a vivid portrait of wartime intrigue, courage, and the high cost of loyalty in a world consumed by conflict.