The world watched when South Africa finally dismantled its system of apartheid, released Nelson Mandela from prison, held free elections and turned control over to the African majority.

What the world didn't know was the tense, dramatic negotiations that led to that point. But those negotiations have been turned into the tense, dramatic film "Endgame," which showed at Sundance and airs Sunday as PBS's "Masterpiece Contemporary" (8 p.m., Ch. 7).

It's riveting drama as Thabo Mbeki (Chiwetel Ejiofor) — who later succeeds Mandela as president of South Africa — faces off against professor Will Esterhuyse (William Hurt) in secret talks as the country teeters on the brink of civil war. Talks facilitated by British businessman and negotiator Michael Young (Johnny Lee Miller), at no small risk to himself.

"Most people I spoke to after (they saw) the piece in Britain — the main thing that everyone says is, 'I had no idea about that,' " Miller said. "That's the nature of secret talks, I guess. But I think the major attraction of the piece is that you are reliving a time that you remember, but you had no idea how it came about."

And it came about in large part because of the efforts of Young, who is hardly a household name like Mandela or even F.W. de Klerk, the last white president of South Africa.

"I personally found apartheid morally repugnant and offensive, but that in itself isn't sufficient," Young said. "Because the next question is, 'What do you do about it?' "

He was not an activist or political leader. Young was the head of public affairs and communications for Consolidated Goldfields, a company that had long exploited the system of apartheid for its own profit.

But he convinced his boss (played by Derek Jacobi) that if South Africa couldn't be changed peacefully, the company would itself be brought to ruin. And Young brought together — and held together — the two wildly antagonistic sides until they hammered out an agreement.

"We can all shout and we can all demonstrate, and that's all to the good because it creates a climate. But I think there was a more specific question, 'What could I do about it?' " Young repeated. "And I think I was in a unique position with this large mining company as their, as it were, licensed liberal to see if we could use that resource to effect the substantive change which I thought was necessary."

With an excellent screenplay by Paula Milne and strong direction by Pete Travis, "Endgame" is a taut thriller despite the fact that we all know how it ends.

The outstanding cast also includes Mark Strong as Niel Barnard, the director of South Africa's National Intelligence Agency, and Clarke Peters as Mandela.

"Endgame" makes for great TV.

"ELI STONE" FANS might be surprised when they hear Jonny Lee Miller speak in "Endgame." He's not affecting a British accent; he was affecting an American accent in "Eli."

"I actually prefer hiding and doing other things," Miller said. "I got so used to doing American for so long. I hate the sound of my own voice. And I think that's true of a lot of actors.

"You know, good work is good work, really. And I'll do any voice and wear any kind of costume."

e-mail: pierce@desnews.com