You may find the scheme at the center of “Deutschland 86” a bit confusing. That’s all right; so does Martin Rauch (Jonas Nay), the reluctant East German spy roped into carrying it out.

As it’s explained to him, his government needs him to facilitate an illicit sale of West German weapons to South Africa, with the assistance of the African National Congress — even though the A.N.C. is bitterly opposed to the apartheid regime, and South Africa is allied with East Germany’s rivals in the Cold War.

Martin is told the deal is for the greater good. But he still has questions. “East, West,” he says. “Who are the good guys?”

In the pulpy-serious “Deutschland 86,” the definition is very flexible.

The 10-episode series, beginning Thursday on SundanceTV, is the follow-up to 2015’s “Deutschland 83,” a German-American coproduction created by the wife-and-husband team Anna and Jörg Winger. That season introduced Martin as a naïve border guard, recruited by his aunt Lenora (Maria Schrader), a cynical, formidable intelligence operative, to infiltrate the West German military in 1983.