Robert Benimoff

Readers will approach “The Woman Who Wasn’t There: The True Story of an Incredible Deception” knowing how it’s going to end. Tania Head, who claimed a place in the public’s heart for having narrowly escaped death in the south tower of the World Trade Center — “America’s most famous survivor,” the authors call her — will be revealed as an impostor.

Her real name is Alicia Head, she is Spanish, and on Sept. 11, 2001, she was in Barcelona attending business school.

The deception itself is not new. It was revealed in The New York Times in 2007. A day earlier, the World Trade Center Survivors’ Network announced that Ms. Head was no longer president of the organization nor associated with it in any way. She then seemed to disappear without a trace.

In “The Woman Who Wasn’t There,” to be released next month, the authors, Robin Gaby Fisher and Angelo J. Guglielmo Jr., tell the story in a straightforward manner, at first relating Ms. Head’s version, then tracing the way her fantastic tale unraveled. (Except for answering fact-checking questions as publication neared, The Times did not assist them.)

Their narrative does, however, yield a surprise: Ms. Head is still around.

That’s not what most people think. The Wikipedia entry on Alicia Esteve Head said (as of Tuesday): “In the documentary ‘The 9/11 Faker,’ broadcast in September 2008, Head’s whereabouts were said to be unknown. In February 2008, an e-mail sent from a Spanish account to members of the World Trade Center Survivors’ Network claimed that Head had committed suicide.”

Mr. Guglielmo, a filmmaker, has been working on a documentary about Ms. Head since before the revelation — initially with her cooperation. Against high odds, he wrote, he spied Ms. Head and her mother on the East Side last Sept. 14. He began following them. “I was intent on talking to Tania or Alicia or any combination,” he wrote. “I was finishing up the documentary and wanted to give her one last chance to tell her side of the story.”

When she finally recognized him, not far from a hotel on East 34th Street where she was apparently staying, she shook her head.

“Don’t come near me, Angelo,” he quoted Ms. Head as saying. “Get away from me.”

His camera running, Mr. Guglielmo said he implored: “How could you show up here during the 10th anniversary? How could you?” After a brief confrontation, he said, he turned off the camera and walked away.