In The Mouth Of The Lion by Frank Gates

An on the run, former South African Special Forces soldier is recruited by the CIA - Michael Memphis wanted to leave his old life behind him.
But the world needs men like him.
It was to be a simple mission. Meet with a top secret scientist in the employ of the hostile and secretive South African Apartheid regime. The scientist is a desperate man attempting to trade sensitive intelligence to the highest bidder. But within hours of landing both men are hunted down by the brutal South African security police, fearful a terrible state-secret might be exposed jeopardizing South Africa’s relations with their Western allies. Allies that consider the South African government absolutely vital in eliminating the Cold War threat of communism on the African continent.
A fact that threatens to overshadow the missing men, leaving their lives hanging in the balance.
That is, unless the two men can escape.
Though faced with extraordinarily few choices, Memphis has been carefully plotting their freedom since their capture - while also planning to deliver and expose an even bigger, far more dangerous evil to the Americans and the world.
High risk, high reward, “In The Mouth Of The Lion” is a nonstop, page-turning high-speed thriller that will have you right in the middle of the action…!

*Looking for familiar ground? You’re on it, if you enjoy reading David Baldacci, Dan Brown’s Robert Langdon, Lee Child’s Jack Reacher, Tom Clancy’s Jack Ryan, Nelson DeMille’s John Corey, Mark Dawson’s John Milton, Vince Flynn’s Mitch Rapp, Mark Greaney’s Gray Man, Gregg Hurwitz’s Orphan X, John Le Carre, Robert Ludlum’s Jason Bourne, John Sandford’s Lucas Davenport, Daniel Silva’s Gabriel Allon, Wayne Stinnett’s Jesse McDermitt, Brad Taylor’s Pike Logan, Brad Thor’s Scot Harvath and Tim Tigner’s Kyle Achilles.