Jessica Rothe (front) appears in a scene from “Happy Death Day 2U.”

“Happy Death Day 2U,” the follow-up to the surprise 2017 hit “Happy Death Day,” is that rare sequel that surpasses the original – a fun, genre-bending excursion that takes the franchise in a different direction that is more enjoyable than the first one.

While the original was more of a “Groundhog Day” slasher film, “2U” takes a science fiction approach that pays homage to the “Back to the Future” films. It’s a turn that works surprisingly well, thanks to a great cast headlined by Jessica Rothe.

She returns as college student Tree Gelbman, who seems to have learned her lesson after having to live the same day over and over again until she could uncover who was trying to kill her.

Tree is now happily involved with Carter (Israel Broussard), but just as things are back to normal, Carter’s roommate Ryan (Phi Vu) shows up convinced he is living the same day over and over again.

It turns out Ryan and his friends Samar and Dre (Suraj Sharma and Sarah Yarkin, who are welcome additions to the cast) have created a time machine that caused Tree’s initial dilemma. When they fire up the time machine again to get Ryan out of his loop, it sends Tree into an alternate dimension where she has to relive the same day she escaped over and over again, with another killer standing in her way.

The only way Tree can escape being trapped in the same day is to figure out a way to fix the time machine (everyone else’s recollections are reset with every day) before anyone else gets murdered.

Sure this sounds a little convoluted, but that’s part of the fun. Writer/director Christopher Landon returns – bringing the same self-awareness that made the first film work. This time it’s a film that knows it’s being a little nerdy – and embraces its nerdiness with glee (even throwing in a few “Back to the Future” Easter eggs along the way).

But like the original, “Happy Death Day 2U” works largely due to Rothe, who once again is having a blast. She has perfect comedic timing when needed, but also shows a more dramatic side when the film takes a few twists that present Tree with some tough choices about which dimension she really wants to be a part of.

Rothe’s fun performance is quite infectious, allowing the audience to overlook the film’s shortcomings – mainly the final act where things get a little too twisty for its own good.

But you can’t fault a film that wants to be creative in ways you wouldn’t have thought possible before – with “Happy Death Day 2U” becoming the first slasher franchise to completely shift genres from one film to the next without ever missing a beat.

Starring: Jessica Rothe, Israel Broussard

Directed by: Christopher Landon

Rating: PG-13 for violence, language, sexual material and thematic elements.

Playing at: Regal Bowling Green Stadium 12, Regal Greenwood Mall Stadium 10, Highland Cinemas (Glasgow)

Grade: B