At Paramount Pictures’ request, the Del Mar Theatre in Santa Cruz was among only 12 theaters in the country — and the only theater in California — to premiere the low-budget, high-fright horror film “Paranormal Activity,” starting Thursday, Sept. 24.

Thrill-seekers, including folks from as far away as Los Angeles and San Diego, assembled downtown for midnight showings throughout the film’s opening weekend, with lines filling the sidewalk for an entire city block.