The Harry Potter films have become the biggest movie franchise in history, and there’s till two to go. The five movies have taken $4.47bn (£2.2bn) around the world, surpassing the $4.44bn (£2.19bn) made by [James Bond's] 22 outings to date. The six Star War films now sit in third place, with takings of $4.23bn (£2bn). [...]