Just 15 months ago, there was “Happy Death Day.” The Blumhouse production wasn’t aiming very high with its mixture of comedy and horror, offering younger audiences their own “Groundhog Day,” fitting a slasher movie set-up for a time loop gimmick. The PG-13 frightener clicked with audiences in the mood for a wacky distraction, giving Halloween 2017 a slight boost at the box office. Terrified of losing such momentum, writer/director Christopher Landon went right back into production, churning out a quickie sequel in “Happy Death Day 2U,” hoping to retain the limited attention span of certain viewers these days. There’s lots of room for improvement, but Landon merely hints at creative escalation with the follow-up, which chases a tale about a killer in a baby mask with another tale about a killer in a baby mask. There’s a heavy “Back to the Future” influence this time around, for everything except sequel quality. Read the rest at Blu-ray.com