I still haven’t seen The Conjuring but I don’t think it is a necessity to see the prequel to understand this film. There’s nothing really unique in The Conjuring 2, except for the song. The story’s predictable, and it does not scare you to the amount you expect from a proper horror film. The sets and atmosphere aren’t really scary either because they’re old school ( rainy nights, dingy cellars.) . It’s a mildly entertaining movie at the most, but not really worth going to the theatre to watch.