This hideous story unfolds in “The Deadly Deception,” produced by Denisce DiIanni, which PBS will telecast this week on “Nova.” How, it asks, “could this experiment have happened?” In a galvanizing hour that includes interviews with survivors and scientists, it offers grim answers. These patients, says University of Wisconsin historian Dr. Vanessa Gamble, “weren’t going to question the government doctors … Who’s going to speak for them?” Certainly not some of their doctors. Even now, Dr. John Cutler insists that the study would eventually have improved “the quality of care for the black community.” The flawed experiment was publicly tolerated for decades. The “first rumblings” of protest came in the 1960s, when Bill Jenkins, an African-American epidemiologist, tried unsuccessfully to interest the media. It took a white health worker, Peter Buxtun, who fed files to a reporter in 1972, to generate an investigation that shut down the project. By then, as many as 100 of the 400 recruits had died of syphilis. “The Deadly Deception” is a quiet, searing indictment of unethical conduct, not just in the medical community, but in society as a whole.