Shipka, Kiernan

This teen slasher comedy with a time-traveling twist can’t muster up enough charisma to make its mash-up concept sing.“Totally Killer,” a time-travel teen slasher comedy, is quick to acknowledge itself as a mash-up of two 20th-century cultural touchstones. “Have you seen the movie ‘Back to the Future?’” Jamie (Kiernan Shipka), the movie’s teenage protagonist, asks a pair of cops, before later making an allusion to “Scream,” Wes Craven’s spooky-season classic. The somewhat gimmicky genre combination may have had the potential to be a winning combo, but “Totally Killer,” directed by Nahnatchka Khan, struggles to muster up enough charisma to stick the landing.After the Sweet Sixteen Killer, who murdered Jamie’s mother’s friends when her mother was a teenager, makes a sudden return on Halloween, Jamie is thrust into a time machine that sends her back to 1987, when the original killings took place. Posing as the new kid in town, Jamie becomes close with the teenage version of her mother (Olivia Holt), hoping to stop the killer before he begins his rampage.The fun premise can make for a passively enjoyable watch during a Halloween binge, but the film mostly feels like it’s just going through the motions. Its ‘80s throwback setting is short on color and life, and its slasher elements lack the choreographic or cinematic oomph to induce any terror, or even tension. Shipka is the unequivocal bright spot, naturally embodying the charm, emotion and wit that made this movie’s forebears shine in the first place.Totally KillerRated R for bloody violence, language, sexual material and teen substance use. Running time: 1 hour 46 minutes. Watch on Amazon Prime Video. More