The sudden and tumultuous end of Brangelina was one of the biggest celebrity stories of 2016; now, the dissolution of Angelina Jolie’s marriage to Brad Pitt is to be the subject of a potentially explosive documentary by filmmaker Ian Halperin.

The 52 year old investigative journalist and best-selling author Halperin announced details of a new film he’s produced that promises to tell the inside story of Brad and Angelina’s decade-long relationship and eventual divorce proceedings.

According to initial reports, the documentary will uncover a lot of dirty laundry. “This is the definitive film about Brangelina and a lot of secrets are going to come out,” a source close to the project told The Sun on Thursday (January 26th).

Brad Pitt Angelina JolieAngelina Jolie and Brad Pitt at the premiere of 'By The Sea' in 2015

Among the bombshells is reportedly the revelation that the Hollywood power couple might have been actually estranged for the best part of a year before their headline-making split in September 2016.

More: Brad Pitt and Angelina Jolie finally agree to keep divorce details private

Halperin previously wrote a book, published in 2009, charting the course of Jolie and Pitt’s relationship. He also wrote Unmasked, about the late Michael Jackson’s final years, which was made into a film called Gone Too Soon after it hit the top of the New York Times’ best-sellers list.

The new project is titled ‘Broken: The Incredible Story of Brangelina’ and set to be broadcast on television around the world, after rights were purchased by Content Media Corporation this month.

Teasing more details, the same source added: “Ian has covered every cough and spit of their relationship and will reveal the real reasons behind Angelina filing for divorce. The biggest shock will be his claim that the couple were apart for more than a year prior to their break-up.

“He and his team have also managed to acquire some never-before-seen footage and interviews with both Brad and Angelina. Lately the pair have been trying to put on a united front and keep their divorce discussions quiet. This is the last thing they need.”

More: Jon Voight says he’s rooting for both daughter Angelina and Brad during divorce proceedings