The 'theatrical event' in two halves is billed as the eighth part of the series. It is based on a new story by JK Rowling, Jack Thorne and John Tiffany, reported Digital Spy.
The synopsis read, "It was always difficult being Harry Potter and it isn't much easier now that he is an overworked employee of the Ministry of Magic, a husband and father of three school-age children.
"While Harry grapples with a past that refuses to stay where it belongs, his youngest son Albus must struggle with the weight of a family legacy he never wanted. As past and present fuse ominously, both father and son learn the uncomfortable truth: sometimes, darkness comes from unexpected places."