Malik quit the group last month (Mar15), and the remaining bandmembers vowed to continue as a four-piece.

Spurlock, who was given unrestricted access to the band while making the One Direction: This Is Us documentary, is convinced they will not continue with the new line-up for long as Styles will break away to forge a solo career, leaving Niall Horan, Louis Tomlinson and Liam Payne to rebrand like hip-hop trio Bell Biv DeVoe, which was created from the ashes of New Edition.

Spurlock tells TMZ.com, "I think they'll stay together for a little bit longer then I think at some point, Harry will probably leave. He'll probably be next and I think that Niall and Louis and (Liam)... I think the three of those guys will become the next Bell Biv DeVoe."