At the time of his split from Angelina Jolie, false rumours flew that Brad Pitt had had an affair with his Allied co-star Marion Cottilard.
The pregnant French actress, who is married to Guillaume Canet, swiftly set the record straight, insisting on Instagram that she had nothing to do with their split.
However, Brad did play away with another Hollywood actress, according to NW magazine, which claims ‘the truth’ came out when after Ange hired a private investigator to tail him for a year.
And the fact that his alleged mistress was an actress was the supposed final straw for Angelina, 41.
“Ange could handle him having flings with random women who posed no real threat to her,” the mag quotes a source as saying. “But this would look like she was being replaced.”
Armed with the supposed evidence, Ange is said to have confronted Brad, 53, with the source claiming he admitted that “some of it was true, some not.”
The allegations reportedly form part of an explosive dossier of leaked evidence from their custody battle, which NW reckons is being shopped around for the highest price.
It comes just days after filmmaker Ian Halperin – who is making a documentary about their split – claimed they’d both been wanting out of their relationship for “a long time.”
An expert in all things Brange, Ian was the author behind the 2009 bestseller Brangelina: The Untold Story of Brad Pitt and Angelina Jolie, and told OK magazine that they were incompatible from the start.
The celebrity biographer tells the publication that Brad and Ange split privately in 2015, with their "toxic" marriage all but over while they filmed By the Sea.
He also reckons Brad was the one who wanted to leave first.
"Angelina became terrified Brad would go public," Ian says of their 2015 break-up.
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"In the two months leading up to her decision to file for divorce, he had threatened to publicly dissolve the relationship six times. She was afraid and she wanted to beat him to the public," he continues, adding that Brad felt betrayed by her decision.