Soon after J.D. Salinger’s death on Jan. 27, revealed that screenwriter Shane Salerno (Shaft) had spent the past five years completing a documentary about the reclusive author. Even more remarkable, Salerno was able to keep the film, which features over 150 interviews with people like Philip Seymour Hoffman, Edward Norton, and Gore Vidal, a secret. According to an insider involved with the project, crew members had to sign “CIA-worthy” non-disclosure agreements, and the filmmakers made sure never to give any post-production facility more than 20% of the film to prevent any leaks.

The movie contains interviews with people close to Salinger who have never spoken on camera and it looks at his writing process since 1965, when he stopped publishing. It also features footage of Salinger, materials belonging to him as well as more than 100 photographs of the rarely seen author. There is no word if Salerno got an interview with the mysterious Salinger himself. “There is no PBS-type narrator, no black background or talking heads,” says the source. “The look, sound, and editorial pacing is consistent with a feature film.” As for a premiere date, filmmakers are hoping to take the film to the Cannes Film Festival in May.