Ice Conspiracy

The night before Saigon fell to the North Vietnamese Army (April 28, 1975), two naval officers, one a Navy SEAL and the other a Special Ops Navy Seabee, along with a South Vietnamese general and a US embassy official (CIA), were instructed to carry out a "black ops" mission. The four completed the mission; however, one of them lost their life who actually knew the real intent of the mission.
The story shifts to 1998 when another member of the team dies of suspicious circumstances, and the two remaining members of the team return to Vietnam to uncover what they really did that last night in South Vietnam.
The plot splits into (1) solving the unsuspecting homicide and (2) what the real reason was for the "black ops" mission.
It concludes with lives being changed, along with a sad twist.