SAN DIEGO (CNS) - The annual festival of pop arts, superheroes and Hollywood hype known as Comic-Con International begins Wednesday evening with a preview night.

The festivities begin at 6 p.m. and will include screenings of pilot episodes of five Warner Bros. television programs scheduled for the 2012-13 season.

The main part of Comic-Con, which is sold out, will run Thursday through Sunday, attracting 126,000 attendees to downtown San Diego.

Fans of the "Twilight" series of books and films have been waiting in line outside the center since Sunday. Among the Thursday highlights is a screening of footage from "The Twilight Saga: Breaking Dawn -- Part 2."

Hollywood studios and television networks will offer previews of their productions throughout the four days of the show.

Authorities suggest using public transportation to go to the event. The Metropolitan Transit System plans to expand its service and is selling special Comic-Con daily transit passes. Also being offered is free shuttle service between the Convention Center and hotels downtown, in Mission Valley, on Harbor Island and Shelter Island.

Comic-Con International is by far the largest annual show at the Convention Center, which is scheduled to begin an expansion project as soon as the end of this year. San Diego tourism officials said the event will result in $75 million in direct spending in the area and $2.6 million in tax revenues.