Some things to expect in a horror movie sequel: a higher body count, cruder shock effects, louder screams, vanishing credibility and loss of narrative coherence.

''I Still Know What You Did Last Summer'' conforms depressingly to type. The follow-up to the phenomenally successful ''I Know What You Did Last Summer'' is an empty, farcical blood bath that's virtually shock-free except for one preposterous plot twist. What is that ominous thudding sound inside the giant clothes dryer? You know what it is without even having to open the door. Maybe one of the kicks of a movie this bad is feeling you're ahead of the game.

Though the original film was no horror classic, its portrait of four North Carolina teen-agers hunted by the victim of a supposedly fatal hit-and-run accident for which they were responsible produced a tingle of recognition. Which of us hasn't at one time or another been so haunted by a guilty secret that we entertain paranoid fantasies of imminent cosmic payback? And Jennifer Love Hewitt, as Julie James, the most conscience-stricken of the four, made quivering, teary-eyed guilt seem almost attractive.

''I Still Know'' finds Julie (Ms. Hewitt once again) still so obsessed with the past that she is having a fresh hallucination every two or three minutes. When her college roommate Karla (the pop singer Brandy) wins a weekend trip to the Bahamas for herself and three friends, Julie jumps at the opportunity to go, even though it means leaving behind her boyfriend, Ray (Freddie Prinze Jr.), who has to work. Besides, Brandy, who takes along her sassy boyfriend, Tyrell (Mekhi Phifer), is pushing a romance between Julie and Will (Matthew Settle), a clean-cut classmate also on the trip, who has a big crush on Julie. Who knows what could blossom between the two while lounging side by side in a tropical paradise?