“Slayers” (* out of four) was a slayingly awful horror thriller about a group of social-media influencers and thrill-seekers (Kara Hayward, Malin Ackerman, Abigail Breslin, and others) who become trapped in the lair of a vicious vampire and the only one who can save them is a legendary vampire hunter (Thomas Jane). Dumb-and-dumber writing and plotting makes this particularly grueling and the in-your-face direction and filmmaking is no help. Jane’s unlikeable character feels like an additional stake to the heart. By this point, his career needs a transfusion of new and fresh blood.