I WATCHED “Zero Dark Thirty” not as a former F.B.I. special agent who spent a decade chasing, interrogating and prosecuting top members of Al Qaeda but as someone who enjoys Hollywood movies. As a movie, I enjoyed it. As history, it’s bunk.

The film opens with the words “Based on Firsthand Accounts of Actual Events.” But the filmmakers immediately pass fiction off as history, when a character named Ammar is tortured and afterward, it’s implied, gives up information that leads to Osama bin Laden.

Ammar is a composite character who bears a strong resemblance to a real-life terrorist, Ammar al-Baluchi. In both the film and real life he was a relative of Bin Laden’s lieutenant, Khalid Shaikh Mohammed. But the C.I.A. has repeatedly said that only three detainees were ever waterboarded. The real Mr. Baluchi was not among them, and he didn’t give up information that led to Bin Laden.

In fact, torture led us away from Bin Laden. After Mr. Mohammed was waterboarded 183 times, he actually played down the importance of the courier who ultimately led us to Bin Laden. Numerous investigations, most recently a 6,300-page classified report by the Senate Select Committee on Intelligence, have reached the same conclusion: enhanced interrogation didn’t work. Portraying torture as effective risks misleading the next generation of Americans that one of our government’s greatest successes came about because of the efficacy of torture. It’s a disservice both to our history and our national security.